Answers for "Error: Expected "payload" to be a plain object. at validate"

Error: Expected "payload" to be a plain object. at validate

const token = jwt.sign(user.toJSON(), config.secret, {
  expiresIn: 604800 // 1 week
});

Error: Expected "payload" to be a plain object. at validate

const token = jwt.sign(user.toJSON(), config.secret, {
  expiresIn: 604800 // 1 week
});