ErrorException in myth auth login

Question

I'm using myth auth library to my login form. When I ran the login it said:

ErrorException Undefined variable: config

here are the code for my view l

<?= $this->extend($config->viewLayout); ?>
<form action="<?= base_url(route_to('login')) ?>" method="post">
                                        <?= csrf_field() ?>
 <?php if ($config->validFields === ['email']): ?>
    <div class="form-group">
       
    <input type="email" class="form-control form-control-user <?php if(session('errors.login')) : ?>is- 
     invalid<?php endif ?>" name="login"  placeholder="<?=lang('Auth.email')?>">
                                                
  <div class="invalid-feedback">
   <?= session('errors.login') ?>
  </div>
  </div>

<?php else: ?>
   <div class="form-group">
     <input type="text" class="form-control <?php if(session('errors.login')) : ?>is-invalid<?php endif ? 
       >" name="login" placeholder="<?=lang('Auth.emailOrUsername')?>">
  <div class="invalid-feedback">
    <?= session('errors.login') ?>
  </div>
  </div>
<?php endif; ?>

Answer 1

In my case, once logged on, it redirected back to the login page with the error above. To solve the issue, I create a public constructor which contains the variable config and pass the variable to the login view.

Public constructor method:

public function __construct()
{
    $this->session = service('session');
    $this->config = config('Auth');
    $this->auth = service('authentication');
}

Public index method:

{
    $data = [
        'config' => $this->config
    ];
    return view('/forms/login', $data);
}

Answer 2

myth\auth\src\convig\auth line 50

public $validFields = [
    'username', 'email'
];

Don't remove 'email'.