ContractVerificationMissingBytecodeError: Failed to send contract verification request.

[satishnvrn]

I'm trying to deploy the SimpleStorage contract using hardhat deploy in Sepolia network and getting the error. All my code resides in this GitHub repo: https://github.com/satishnvrn/hardhat-smart-contracts

My node version is 18.16.0

I tried to wait for 20 blocks to confirm and verify my contract. This is the error I get when I run yarn deploy --network sepolia:

Deploying Simple Storage...
Deployed simple storage to xxxxxxxxxxxxxxxxxxxxxxxxx
waiting for txes
20 transactions approved!
ContractVerificationMissingBytecodeError: Failed to send contract verification request.
Endpoint URL: https://api-sepolia.etherscan.io/api
Reason: The Etherscan API responded that the address xxxxxxxxxxxxxxxxxxxxxxxxx does not have bytecode.
This can happen if the contract was recently deployed and this fact hasn't propagated to the backend yet.
Try waiting for a minute before verifying your contract. If you are invoking this from a script,
try to wait for five confirmations of your contract deployment transaction before running the verification subtask.
    at Etherscan.verify (/Users/satishnvrn/Documents/Projects/hh-sat/hardhat-smart-contracts/node_modules/@nomicfoundation/hardhat-verify/src/etherscan.ts:108:13)
    at processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async SimpleTaskDefinition.action (/Users/satishnvrn/Documents/Projects/hh-sat/hardhat-smart-contracts/node_modules/@nomicfoundation/hardhat-verify/src/index.ts:478:33)
    at async Environment._runTaskDefinition (/Users/satishnvrn/Documents/Projects/hh-sat/hardhat-smart-contracts/node_modules/hardhat/src/internal/core/runtime-environment.ts:330:14)
    at async Environment.run (/Users/satishnvrn/Documents/Projects/hh-sat/hardhat-smart-contracts/node_modules/hardhat/src/internal/core/runtime-environment.ts:163:14)
    at async SimpleTaskDefinition.action (/Users/satishnvrn/Documents/Projects/hh-sat/hardhat-smart-contracts/node_modules/@nomicfoundation/hardhat-verify/src/index.ts:305:9)
    at async Environment._runTaskDefinition (/Users/satishnvrn/Documents/Projects/hh-sat/hardhat-smart-contracts/node_modules/hardhat/src/internal/core/runtime-environment.ts:330:14)
    at async Environment.run (/Users/satishnvrn/Documents/Projects/hh-sat/hardhat-smart-contracts/node_modules/hardhat/src/internal/core/runtime-environment.ts:163:14)
    at async SimpleTaskDefinition.action (/Users/satishnvrn/Documents/Projects/hh-sat/hardhat-smart-contracts/node_modules/@nomicfoundation/hardhat-verify/src/index.ts:554:7)
    at async Environment._runTaskDefinition (/Users/satishnvrn/Documents/Projects/hh-sat/hardhat-smart-contracts/node_modules/hardhat/src/internal/core/runtime-environment.ts:330:14)
updatedValue 10n

I tried it multiple times and it is consistently giving this error. I even deleted artifacts and cache folder and retried. No luck

[alfaqi]

See here (Bytecode not found error in verification request (chapter 6) #5720)

[satishnvrn]

Thanks. The problem is the same but still looking for an answer.

[alfaqi]

I made some changes based on https://github.com/PatrickAlphaC/hardhat-simple-storage-fcc/tree/typescript
the main thing to focus is ethers version.

and add this line customChains: [], to hardhat.config.ts
in case you face TypeError: customChains is not iterable error

 etherscan: {
    apiKey: ETHERSCAN_API_KEY,
    customChains: [],
  },

and it works fine.

[satishnvrn]

Can you tell me what changes you made exactly and did it work by changing ethers version? Is it possible to fix this using the latest version?

[alfaqi]

package.json

    "ethers": "^5.0.0",
    "@nomiclabs/hardhat-etherscan": "^3.0.0",
    "@typechain/ethers-v5": "^9.0.0",
    "@nomiclabs/hardhat-ethers": "^2.0.4",

hardhat.config.ts

import('@nomiclabs/hardhat-etherscan');
import { task, HardhatUserConfig } from 'hardhat/config';
import 'dotenv/config';
import '@typechain/hardhat';
import '@nomiclabs/hardhat-ethers';

  etherscan: {
    apiKey: ETHERSCAN_API_KEY,
    customChains: [],
  },

deploy.ts

  const SimpleStorageFactory = await ethers.getContractFactory('SimpleStorage');
  console.log('Deploying contract...');
  const simpleStorage = await SimpleStorageFactory.deploy();
  
  await simpleStorage.deployed();

  const deployedAddress = await simpleStorage.address;
  console.log('Deployed simple storage to', deployedAddress);
  if (
    network.config.chainId === 11155111 &&
    process.env.ETHERSCAN_API_KEY
  ) {
    console.log('waiting for txes');
    await simpleStorage.deployTransaction.wait(6);
    console.log('6 transactions approved!');
    await verify(deployedAddress, []);
  }

those the change that I made.
and the version of ethers not latest version, but version 5 that it's work perfectly.

I hope it helps

[alfaqi]

package.json file

{
  "name": "hardhat-smart-contracts",
  "packageManager": "yarn@3.5.1",
  "devDependencies": {
    "@nomicfoundation/hardhat-chai-matchers": "^2.0.0",
    "@nomicfoundation/hardhat-network-helpers": "^1.0.0",
    "@nomicfoundation/hardhat-toolbox": "^3.0.0",
    "@nomicfoundation/hardhat-verify": "^1.0.1",
    "@typechain/hardhat": "^8.0.0",
    "@types/chai": "^4.2.0",
    "@types/mocha": ">=9.1.0",
    "@types/node": ">=12.0.0",
    "chai": "^4.2.0",
    
    "ethers": "^5.0.0",
    "@nomiclabs/hardhat-etherscan": "^3.0.0",
    "@typechain/ethers-v5": "^9.0.0",
    "@nomiclabs/hardhat-ethers": "^2.0.4",

    "hardhat": "^2.15.0",
    "hardhat-gas-reporter": "^1.0.8",
    "prettier": "^2.8.8",
    "prettier-plugin-solidity": "^1.1.3",
    "solidity-coverage": "^0.8.0",
    "ts-node": ">=8.0.0",
    "typechain": "^8.1.0",
    "typescript": ">=4.5.0"
  },
  "dependencies": {
    "dotenv": "^16.3.1"
  },
  "scripts": {
    "deploy": "hardhat run scripts/deploy.ts"
  }
}

[satishnvrn]

Thanks. That worked for me as well. I think that issue is with ethers v6. I will try to open an issue with ethers or hardhat and close this discussion.