Fatal error: Uncaught Error: Interface "Illuminate\Contracts\Mail\Mailable" not found in C:\xampp\htdocs\public\vendor\laravel\framework\src\Illuminate\Mail\Mailable.php:30 Stack trace: #0 {main} thrown in C:\xampp\htdocs\public\vendor\laravel\framework\src\Illuminate\Mail\Mailable.php on line 30