护照这个.set调用setPassword时不是函数

const {promisify} = require('es6-promisify');

exports.resetPassword = async (req, res) => {
  const user = await User.findOne({
    resetPasswordToken: req.params.token,
    resetPasswordExpires: { $gt: Date.now() }
  });
  
  if (!user) {
    req.flash('error', 'Password reset is invalid or has expired');
    return res.redirect('/login');
  }

  const setPassword = promisify(user.setPassword, user);
  await setPassword(req.body.password);

  user.resetPasswordToken = undefined;
  user.resetPasswordExpires = undefined;
  const updatedUser = await user.save();
  await req.login(updatedUser);
  req.flash('success', 'Your password has been reset!');
  res.redirect('/login');
}

TypeError: this.set is not a function
    at Promise.resolve.then.then.then.then.then.salt (...\node_modules\passport-local-mongoose\index.js:98:14)
From previous event:
    at exports.updatePassword (...auth.controller.js:146:9)
    at 
    at process._tickCallback (internal/process/next_tick.js:188:7)