To make this simple, don’t use asset() or url() helpers in Laravel config files. Using that will throw you the error given below while using artisan command

In UrlGenerator.php line 120:

  Argument 2 passed to Illuminate\Routing\UrlGenerator::__construct() must be an instance of Illuminate\Http\Request, null given, called in C:\wamp64\www\project\vendor\laravel\framework\src\Illumi
  nate\Routing\RoutingServiceProvider.php on line 65