Why am I getting "Error 500" in Postman? User not defined

this is my code : who is my problem !

  const jwt = require("jsonwebtoken");

const verifyToken = (req, res, next) => {

  const authHeader = req.headers.token;
  if (authHeader) {
    const token = authHeader.split(" ")[1];
    jwt.verify(token, process.env.JWT_SEC, (err, user) => {
      if (err) res.status(403).json("Token is not valid!");
      req.user = user;
      next();
    });
  } else {
    return res.status(401).json("You are not Authenticated!");
  }
};

const verifyTokenAndAuthorization = (req, res, next) => {
  verifyToken(req, res, () => {
    if (req.user.id === req.params.id || req.user.isAdmin) {
      next();
    } else {
      res.status(403).json("You are not alowed to do that!");
    }
  });
};

const verifyTokenAndAdmin = (res, req, next) => {
  verifyToken(req, res, () => {
    if (req.user.isAdmin) {
      next();
    } else {
      res.status(403).json("You are not alowed to do that not admin!");
    }
  });
};

module.exports = {
  verifyToken,
  verifyTokenAndAuthorization,
  verifyTokenAndAdmin,
};

I checked my Postman and I'm sure everything is correct but I can't post or get or put anything yet.
Could my problem be my findByIdAndUpdate?