Request Token missing error when trying to login.

[RanvirChoudhary]

i am getting request token missing error when trying to login. here's how i'm saving the tokens

const oauth_token_secret = "<i have written random numbers and letters here in my code as a string>";

app.listen(3000, () => {});

app.get("/callback", (req, res) => {
  const { oauth_token, oauth_verifier } = req.query;

  if (!oauth_token || !oauth_verifier || !oauth_token_secret) {
    return res.status(400).send("You denied the app or your session expired!");
  }

  const client = new TwitterApi({
    appKey: process.env.API_KEY,
    appSecret: process.env.API_KEY_SECRET,
    accessToken: oauth_token,
    accessSecret: oauth_token_secret,
  });

  client
    .login(oauth_verifier)
    .then(({ client: loggedClient, accessToken, accessSecret }) => {
      let tokens = {
        accessToken: accessToken,
        accessSecret: accessSecret,
        oauth_verifier: oauth_verifier
      };
      fs.writeFileSync("./tokens.json", JSON.stringify(tokens), (err) => console.error(err));
      // loggedClient.v2.tweet("hello this is test number: 3"); << this works. i stay stuck
      //on the redirect page, but the tweet is sent
      res.status(200).send("chad like success")
    })
    .catch((err) => {
      console.log(console.error(err))
      res.status(403).send("Invalid verifier or access tokens!")
    });
});

i want to access my tokens in another file. here's how i access them.

const tokens = JSON.parse(fs.readFileSync("./tokens.json"));

const { accessToken, accessSecret, oauth_verifier } = tokens;

const client = new TwitterApi({
  appKey: process.env.API_KEY,
  appSecret: process.env.API_KEY_SECRET,
  accessToken: accessToken,
  accessSecret: accessSecret,
});

const {client: Bot} = await client.login(oauth_verifier); //i think this is line throwing the error

//do something

the first snippet runs fine (the callback snippet). it saves the tokens and all that. but the second code snippet throws an error. I can't figure this out.

to avoid confusion PLEASE UNDERSTAND THAT I AM NOT PROVIDING THIS AS A SERVICE. I AM NOT PROVIDING THIS CODE AS A SERVICE.