Assign role to new created user after signup

Hey wishing you a great day, i am trying to assign a role to new created users using a rule called “Set roles to a user” built by default and i edit it as follow :

function setRolesToUser(user, context, callback) {
  // Roles should only be set to verified users.
  if (! {
    return callback(null, user, context);

  user.app_metadata = user.app_metadata || {};
  // You can add a Role based on what you want
  // In this case I check domain
  const addRolesToUser = function (user) {

    if (
    ) {
      return ['customer'];
    return ['user'];

  const roles = addRolesToUser(user);

  user.app_metadata.roles = roles;
    .updateAppMetadata(user.user_id, user.app_metadata)
    .then(function () {
      context.idToken[''] = user.app_metadata.roles;
      callback(null, user, context);
    .catch(function (err) {

i try to make some edit to it to ignore if the user is verified or not as well as assigning every new user the role “customer” but when i test it i get “ERROR: The user does not exist.” where is the issue?