[RESOLVED] Error : non-payable method cannot override value

[ripcordChain]

Hi everyone!

I try to interact with Kyber DMM contracts (Uniswap fork) and I face this error :
Unhandled Rejection (Error): non-payable method cannot override value (operation="overrides.value", value="0x056bc75e2d63100000", code=UNSUPPORTED_OPERATION, version=contracts/5.5.0)
It happens when I call the swapExactTokensForTokens method. I searched for hours but I didn't understand what is and where is the issue.
Could you please help me?
My code :

import { useEffect } from "react";
import { utils, providers, Wallet, Contract, BigNumber } from "ethers";
import {
  ChainId,
  Fetcher,
  Route,
  Trade,
  TokenAmount,
  TradeType,
  Percent,
  JSBI,
  Token,
  Pair,
} from "@dynamic-amm/sdk";

const App = () => {
  //**** create provider for mumbai */
  const alchemyKey: string = process.env
    .REACT_APP_ALCHEMY_KEY!.toString()
    .trim();
  const provider = new providers.AlchemyProvider(
    80001,
    alchemyKey
  ) as providers.AlchemyProvider;
  const chainId = ChainId.MUMBAI as number;

  //**** transaction settings */
  const addrFactory: string = utils.getAddress(
    "0x7900309d0b1c8D3d665Ae40e712E8ba4FC4F5453"
  ); // dmm factory contract on mumbai
  const addrTokenA: string = utils.getAddress(
    "0x001b3b4d0f3714ca98ba10f6042daebf0b1b7b6f"
  ); // dai on mumbai
  const addrTokenB: string = utils.getAddress(
    "0x2058a9d7613eee744279e3856ef0eada5fcbaa7e"
  ); // usdc on mumbai

  //**** async function to swap */
  const getDatas = async () => {
    // define tokens for swap
    const tokenA: Token = await Fetcher.fetchTokenData(
      chainId,
      addrTokenA,
      provider,
      "DAI",
      "DAI stablecoin"
    ); // dai token object
    const tokenB: Token = await Fetcher.fetchTokenData(
      chainId,
      addrTokenB,
      provider,
      "USDC",
      "USDC stablecoin"
    ); // usdc token object
    // define Pair[] object [dai, usdc]
    const pair: Pair[] = await Fetcher.fetchPairData(
      tokenA,
      tokenB,
      addrFactory,
      provider
    );
    // define route object [dai, usdc]
    const route = new Route(pair, tokenA, tokenB) as Route;
    // define initial input amount in dai
    // const base: bigint = BigInt(Math.pow(10, route.path[0].decimals));
    // const amountInValue: BigNumber = BigNumber.from(100).mul(base); // 100 * 10^18 == 100 dai
    const amountInValue: BigNumber = utils.parseUnits(
      "100.0",
      route.path[0].decimals
    );
    const amountIn: TokenAmount = new TokenAmount(
      tokenA,
      amountInValue.toBigInt()
    );
    // define trade object
    const trade = new Trade(route, amountIn, TradeType.EXACT_INPUT) as Trade;
    // define slippage settings = 0.5%
    const slippageTolerance: Percent = new Percent("50", "10000");
    // compute final minimum output amount
    const amountOutMin: JSBI = trade.minimumAmountOut(slippageTolerance).raw;
    // needs to be converted to e.g. hex
    const amountOutMinHex: string = BigNumber.from(
      amountOutMin.toString()
    ).toHexString();
    // get related pools adresses array for this pair of tokens
    const poolsPath: string[] = await Fetcher.fetchPairAddresses(
      tokenA,
      tokenB,
      addrFactory,
      provider
    );
    // define array of tokens adresses
    const path: string[] = [tokenA.address, tokenB.address];
    // define recipient address for swap
    const to: string = utils.getAddress(
      "0x..."
    );
    // define deadline for transaction < 15'
    const block = (await provider.getBlock("latest")) as providers.Block;
    const deadline: number = block.timestamp + 15;
    // compute input amount -> for exact input trades, this value should be passed as amountIn
    // (TokenAmount type) to router functions.
    const inputAmount: JSBI = trade.inputAmount.raw;
    console.log("trade.inputAmount.raw", inputAmount);
    // needs to be converted to e.g. hex
    const inputAmountHex: string = BigNumber.from(
      inputAmount.toString()
    ).toHexString();
    // define options for swap transaction
    interface IOptionsSwapTx {
      value: string;
      gasPrice: BigNumber;
      gasLimit: BigNumber;
    }
    const optionsSwapTx: IOptionsSwapTx = {
      value: inputAmountHex,
      gasPrice: utils.parseUnits("30.0", "gwei"),
      gasLimit: utils.parseUnits("0.02", "gwei"),
    };
    // define signer for swap transaction
    const signer = Wallet.fromMnemonic(
      process.env.REACT_APP_MNEMONIC!,
      process.env.REACT_APP_ACCOUNT_PATH!
    ) as Wallet;
    // define account
    const account = signer.connect(provider) as Wallet;
    // define dmm Router contract
    const DmmRouter: string[] = [
      "function swapExactTokensForTokens(uint amountIn, uint amountOutMin, address[] calldata poolsPath, address[] calldata path, address to, uint deadline)",
    ];
    const DmmRouterInterface = new utils.Interface(
      DmmRouter
    ) as utils.Interface;
    const dmm = new Contract(
      utils.getAddress("0xD536e64EAe5FBc62E277167e758AfEA570279956"),
      DmmRouterInterface,
      account
    ) as Contract;
    // get the approve for dai token and
    const tokenAcontract = new Contract(
      tokenA.address,
      ["function approve(address spender, uint amount) public returns(bool)"],
      account
    );
    const askApprove = await tokenAcontract.approve(
      dmm.address,
      amountInValue.toBigInt(),
      {
        gasPrice: optionsSwapTx.gasPrice,
        gasLimit: optionsSwapTx.gasLimit,
      }
    );
    const receiptApprove = await askApprove.wait();
    // swap execution
    const txSwap = await dmm.swapExactTokensForTokens(
      inputAmountHex,
      amountOutMinHex,
      poolsPath,
      path,
      to,
      deadline,
      optionsSwapTx
    );
    console.log(`Transaction hash: ${txSwap.hash}`);
    const receiptTxSwap = await txSwap.wait();
    console.log(`Transaction was mined in block ${receiptTxSwap.blockNumber}`);
  };

  useEffect(() => {
    getDatas();
  }, []);

  return <div className="App">test</div>;
};

[zemse]

value means ether, so the method swapExactTokensForTokens in uniswap's router does not accept ether, it is asking you to provide ERC20 tokens for swapping them to other ERC20 tokens. So you should not transfer ETH (by providing any value override). transfer ERC20 tokens to the smart contract. Does that make sense?

If you are swapping tokenA for tokenB, then you have to use ERC20 Approve, which seems you are already using. So just remove the value override.

[ripcordChain]

Yeaaah! This first issue has gone :)
Well, I have another error message but I was looking for the solution for hours.
Now I succeed to create a transaction but it failed with this error :
Uncaught (in promise) Error: transaction failed (transactionHash="0xae4b035ed2836a4756cd8ba248ed024545ca491d24a13d135f0ce97aee09523e", transaction={"nonce":142,"gasPrice":{"type":"BigNumber","hex":"0x06fc23ac00"},"gasLimit":{"type":"BigNumber","hex":"0x01312d00"},"to":"0xD536e64EAe5FBc62E277167e758AfEA570279956","value":{"type":"BigNumber","hex":"0x00"},"data":"0x...","chainId":80001,"v":160038,"r":"0x...","s":"0x...","from":"0x...","hash":"0x...","type":null,"confirmations":0}, receipt={"to":"0x...","from":"0x...","contractAddress":null,"transactionIndex":0,"gasUsed":{"type":"BigNumber","hex":"0x6056"},"logsBloom":"0x...","blockHash":"0x...","transactionHash":"0x...","logs":[{"transactionIndex":0,"blockNumber":20496448,"transactionHash":"0x...","address":"0x...","topics":["0x...","0x...","0x..."],"data":"0x...","logIndex":0,"blockHash":"0x..."}],"blockNumber":20496448,"confirmations":1,"cumulativeGasUsed":{"type":"BigNumber","hex":"0x6056"},"effectiveGasPrice":{"type":"BigNumber","hex":"0x06fc23ac00"},"status":0,"type":0,"byzantium":true}, code=CALL_EXCEPTION, version=providers/5.5.0)

[ripcordChain]

So, the tx return this error Fail with error 'DMMRouter: EXPIRED'
When I look in the Kyber Dmm smart contract this error is thrown in this modifier:

modifier ensure(uint256 deadline) {
  require(deadline >= block.timestamp, "DMMRouter: EXPIRED");
    _;
}

I think my deadline value is not sufficient. I define it like that:

const block = (await provider.getBlock("latest")) as providers.Block;
const deadline: number = block.timestamp + 15;

I modified it:
const deadline = Math.floor(Date.now() / 1000) + 60 * 20;
And it works perfectly now!
Thank you again!

[priyankaj1910]

I am trying to swapTokensForExactETH and running in the same issue. Here is my code set. Can anyone help? @Sm4rtC0ntr4ct @zemse

`const { ethers } = require("ethers")
const path1 = require("path");
const UNISWAP = require("@uniswap/sdk")
const fs = require('fs');
const { Token, WETH, Fetcher, Route, Trade, TokenAmount, TradeType, Percent} = require("@uniswap/sdk");
const { getAddress } = require("ethers/lib/utils");
const QUICKNODE_HTTP_ENDPOINT = "https://rinkeby.infura.io/v3/XX"
let provider = new ethers.providers.getDefaultProvider(QUICKNODE_HTTP_ENDPOINT)

const privateKey = "XXX";//fs.readFileSync(".secret").toString().trim()
const wallet = new ethers.Wallet(privateKey, provider)

UNISWAP_ROUTER_ADDRESS = "0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D"
UNISWAP_ROUTER_ABI = [{"inputs":[{"internalType":"address","name":"_factory","type":"address"},{"internalType":"address","name":"_WETH","type":"address"}],"stateMutability":"nonpayable","type":"constructor"},{"inputs":[],"name":"WETH","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"tokenA","type":"address"},{"internalType":"address","name":"tokenB","type":"address"},{"internalType":"uint256","name":"amountADesired","type":"uint256"},{"internalType":"uint256","name":"amountBDesired","type":"uint256"},{"internalType":"uint256","name":"amountAMin","type":"uint256"},{"internalType":"uint256","name":"amountBMin","type":"uint256"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"addLiquidity","outputs":[{"internalType":"uint256","name":"amountA","type":"uint256"},{"internalType":"uint256","name":"amountB","type":"uint256"},{"internalType":"uint256","name":"liquidity","type":"uint256"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"token","type":"address"},{"internalType":"uint256","name":"amountTokenDesired","type":"uint256"},{"internalType":"uint256","name":"amountTokenMin","type":"uint256"},{"internalType":"uint256","name":"amountETHMin","type":"uint256"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"addLiquidityETH","outputs":[{"internalType":"uint256","name":"amountToken","type":"uint256"},{"internalType":"uint256","name":"amountETH","type":"uint256"},{"internalType":"uint256","name":"liquidity","type":"uint256"}],"stateMutability":"payable","type":"function"},{"inputs":[],"name":"factory","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"amountOut","type":"uint256"},{"internalType":"uint256","name":"reserveIn","type":"uint256"},{"internalType":"uint256","name":"reserveOut","type":"uint256"}],"name":"getAmountIn","outputs":[{"internalType":"uint256","name":"amountIn","type":"uint256"}],"stateMutability":"pure","type":"function"},{"inputs":[{"internalType":"uint256","name":"amountIn","type":"uint256"},{"internalType":"uint256","name":"reserveIn","type":"uint256"},{"internalType":"uint256","name":"reserveOut","type":"uint256"}],"name":"getAmountOut","outputs":[{"internalType":"uint256","name":"amountOut","type":"uint256"}],"stateMutability":"pure","type":"function"},{"inputs":[{"internalType":"uint256","name":"amountOut","type":"uint256"},{"internalType":"address[]","name":"path","type":"address[]"}],"name":"getAmountsIn","outputs":[{"internalType":"uint256[]","name":"amounts","type":"uint256[]"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"amountIn","type":"uint256"},{"internalType":"address[]","name":"path","type":"address[]"}],"name":"getAmountsOut","outputs":[{"internalType":"uint256[]","name":"amounts","type":"uint256[]"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"amountA","type":"uint256"},{"internalType":"uint256","name":"reserveA","type":"uint256"},{"internalType":"uint256","name":"reserveB","type":"uint256"}],"name":"quote","outputs":[{"internalType":"uint256","name":"amountB","type":"uint256"}],"stateMutability":"pure","type":"function"},{"inputs":[{"internalType":"address","name":"tokenA","type":"address"},{"internalType":"address","name":"tokenB","type":"address"},{"internalType":"uint256","name":"liquidity","type":"uint256"},{"internalType":"uint256","name":"amountAMin","type":"uint256"},{"internalType":"uint256","name":"amountBMin","type":"uint256"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"removeLiquidity","outputs":[{"internalType":"uint256","name":"amountA","type":"uint256"},{"internalType":"uint256","name":"amountB","type":"uint256"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"token","type":"address"},{"internalType":"uint256","name":"liquidity","type":"uint256"},{"internalType":"uint256","name":"amountTokenMin","type":"uint256"},{"internalType":"uint256","name":"amountETHMin","type":"uint256"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"removeLiquidityETH","outputs":[{"internalType":"uint256","name":"amountToken","type":"uint256"},{"internalType":"uint256","name":"amountETH","type":"uint256"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"token","type":"address"},{"internalType":"uint256","name":"liquidity","type":"uint256"},{"internalType":"uint256","name":"amountTokenMin","type":"uint256"},{"internalType":"uint256","name":"amountETHMin","type":"uint256"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"removeLiquidityETHSupportingFeeOnTransferTokens","outputs":[{"internalType":"uint256","name":"amountETH","type":"uint256"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"token","type":"address"},{"internalType":"uint256","name":"liquidity","type":"uint256"},{"internalType":"uint256","name":"amountTokenMin","type":"uint256"},{"internalType":"uint256","name":"amountETHMin","type":"uint256"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"},{"internalType":"bool","name":"approveMax","type":"bool"},{"internalType":"uint8","name":"v","type":"uint8"},{"internalType":"bytes32","name":"r","type":"bytes32"},{"internalType":"bytes32","name":"s","type":"bytes32"}],"name":"removeLiquidityETHWithPermit","outputs":[{"internalType":"uint256","name":"amountToken","type":"uint256"},{"internalType":"uint256","name":"amountETH","type":"uint256"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"token","type":"address"},{"internalType":"uint256","name":"liquidity","type":"uint256"},{"internalType":"uint256","name":"amountTokenMin","type":"uint256"},{"internalType":"uint256","name":"amountETHMin","type":"uint256"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"},{"internalType":"bool","name":"approveMax","type":"bool"},{"internalType":"uint8","name":"v","type":"uint8"},{"internalType":"bytes32","name":"r","type":"bytes32"},{"internalType":"bytes32","name":"s","type":"bytes32"}],"name":"removeLiquidityETHWithPermitSupportingFeeOnTransferTokens","outputs":[{"internalType":"uint256","name":"amountETH","type":"uint256"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"tokenA","type":"address"},{"internalType":"address","name":"tokenB","type":"address"},{"internalType":"uint256","name":"liquidity","type":"uint256"},{"internalType":"uint256","name":"amountAMin","type":"uint256"},{"internalType":"uint256","name":"amountBMin","type":"uint256"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"},{"internalType":"bool","name":"approveMax","type":"bool"},{"internalType":"uint8","name":"v","type":"uint8"},{"internalType":"bytes32","name":"r","type":"bytes32"},{"internalType":"bytes32","name":"s","type":"bytes32"}],"name":"removeLiquidityWithPermit","outputs":[{"internalType":"uint256","name":"amountA","type":"uint256"},{"internalType":"uint256","name":"amountB","type":"uint256"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"amountOut","type":"uint256"},{"internalType":"address[]","name":"path","type":"address[]"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"swapETHForExactTokens","outputs":[{"internalType":"uint256[]","name":"amounts","type":"uint256[]"}],"stateMutability":"payable","type":"function"},{"inputs":[{"internalType":"uint256","name":"amountOutMin","type":"uint256"},{"internalType":"address[]","name":"path","type":"address[]"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"swapExactETHForTokens","outputs":[{"internalType":"uint256[]","name":"amounts","type":"uint256[]"}],"stateMutability":"payable","type":"function"},{"inputs":[{"internalType":"uint256","name":"amountOutMin","type":"uint256"},{"internalType":"address[]","name":"path","type":"address[]"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"swapExactETHForTokensSupportingFeeOnTransferTokens","outputs":[],"stateMutability":"payable","type":"function"},{"inputs":[{"internalType":"uint256","name":"amountIn","type":"uint256"},{"internalType":"uint256","name":"amountOutMin","type":"uint256"},{"internalType":"address[]","name":"path","type":"address[]"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"swapExactTokensForETH","outputs":[{"internalType":"uint256[]","name":"amounts","type":"uint256[]"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"amountIn","type":"uint256"},{"internalType":"uint256","name":"amountOutMin","type":"uint256"},{"internalType":"address[]","name":"path","type":"address[]"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"swapExactTokensForETHSupportingFeeOnTransferTokens","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"amountIn","type":"uint256"},{"internalType":"uint256","name":"amountOutMin","type":"uint256"},{"internalType":"address[]","name":"path","type":"address[]"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"swapExactTokensForTokens","outputs":[{"internalType":"uint256[]","name":"amounts","type":"uint256[]"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"amountIn","type":"uint256"},{"internalType":"uint256","name":"amountOutMin","type":"uint256"},{"internalType":"address[]","name":"path","type":"address[]"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"swapExactTokensForTokensSupportingFeeOnTransferTokens","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"amountOut","type":"uint256"},{"internalType":"uint256","name":"amountInMax","type":"uint256"},{"internalType":"address[]","name":"path","type":"address[]"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"swapTokensForExactETH","outputs":[{"internalType":"uint256[]","name":"amounts","type":"uint256[]"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"amountOut","type":"uint256"},{"internalType":"uint256","name":"amountInMax","type":"uint256"},{"internalType":"address[]","name":"path","type":"address[]"},{"internalType":"address","name":"to","type":"address"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"swapTokensForExactTokens","outputs":[{"internalType":"uint256[]","name":"amounts","type":"uint256[]"}],"stateMutability":"nonpayable","type":"function"},{"stateMutability":"payable","type":"receive"}]
//fs.readFileSync(path.resolve(__dirname,"./abis/router.json")).toString()
UNISWAP_ROUTER_CONTRACT = new ethers.Contract(UNISWAP_ROUTER_ADDRESS, UNISWAP_ROUTER_ABI, provider)

const DAI = new Token(
UNISWAP.ChainId.RINKEBY,
"0xB6A8c6Af2781eb9F9F9593351605269835C3A47B",
18
);

async function swapTokens(token1, token2, amount, slippage = "50") {

try {
    const pair = await Fetcher.fetchPairData(token1, token2, provider); //creating instances of a pair
    const route = await new Route([pair], token2); // a fully specified path from input token to output token
    let amountOut = ethers.utils.parseEther(amount.toString()); //helper function to convert ETH to Wei
    amountOut = amountOut.toString()
    
    const slippageTolerance = new Percent(slippage, "10000"); // 50 bips, or 0.50% - Slippage tolerance

    const trade = new Trade( //information necessary to create a swap transaction.
            route,
            new TokenAmount(token2, amountOut),
            TradeType.EXACT_INPUT
    );

    const amountOutMin = trade.minimumAmountOut(slippageTolerance).raw; // needs to be converted to e.g. hex
    const amountOutMinHex = ethers.BigNumber.from(amountOutMin.toString()).toHexString();

    const amountInMax = trade.maximumAmountIn(slippageTolerance).raw; // needs to be converted to e.g. hex
    const amountInMaxHex = ethers.BigNumber.from(amountInMax.toString()).toHexString();

    const path = [token2.address, token1.address]; //An array of token addresses
    const to = wallet.address; // should be a checksummed recipient address
    const deadline = Math.floor(Date.now() / 1000) + 60 * 20; // 20 minutes from the current Unix time
    const value = trade.inputAmount.raw; // // needs to be converted to e.g. hex
    const valueHex = await ethers.BigNumber.from(value.toString()).toHexString(); //convert to hex string

    //Return a copy of transactionRequest, The default implementation calls checkTransaction and resolves to if it is an ENS name, adds gasPrice, nonce, gasLimit and chainId based on the related operations on Signer.
    // const rawTxn = await UNISWAP_ROUTER_CONTRACT.populateTransaction.swapExactETHForTokens(amountOutMinHex, path, to, deadline, {
    //     value: valueHex
    // })

    const rawTxn = await UNISWAP_ROUTER_CONTRACT.populateTransaction.swapTokensForExactETH(amountOut, amountInMaxHex,path, to, deadline, {
        value: valueHex
    })

    //Returns a Promise which resolves to the transaction.
    let sendTxn = (await wallet).sendTransaction(rawTxn)
    

    //Resolves to the TransactionReceipt once the transaction has been included in the chain for x confirms blocks.
    let reciept = (await sendTxn).wait()

    //Logs the information about the transaction it has been mined.
    if (reciept) {
        console.log(" - Transaction is mined - " + '\n' 
        + "Transaction Hash:", (await sendTxn).hash
        + '\n' + "Block Number: " 
        + (await reciept).blockNumber + '\n' 
        + "Navigate to https://rinkeby.etherscan.io/txn/" 
        + (await sendTxn).hash, "to see your transaction")
    } else {
        console.log("Error submitting transaction")
    }

} catch(e) {
    console.log(e)
}

}

//swapTokens(WETH[DAI.chainId],DAI, 0.2) //first argument = token we want, second = token we have, the amount we want

swapTokens(DAI,WETH[DAI.chainId], 0.2)`

[zemse]

The value override means amount of eth that you want to send. This method does not need eth, it needs ERC20 tokens. For safety reasons to prevent loss of your eth, the function gives you error.

// you need to approve tokens so that router contract can pull them from your wallet
await DAI.approve(UNISWAP_ROUTER_CONTRACT.address, amountInMaxHex);

await UNISWAP_ROUTER_CONTRACT.populateTransaction.swapTokensForExactETH(amountOut, amountInMaxHex,path, to, deadline, {
  // value: valueHex // you need to remove this line
})

[Ghassanee]

@priyankaj1910 Hi did you find a solution for it ?
if so can you please share it with us