title: Laravel 6 : A facade root has not been set
body: <p>I have migrate my website from Laravel 5.8 to Laravel 6, after a <strong>composer update</strong> i have this error on the website and also with just a command <strong>php artisan</strong> :</p>
  
  <pre><code>PHP Fatal error:  Uncaught RuntimeException: A facade root has not been set. in /var/www/html/vendor/laravel/framework/src/Illuminate/Support/Facades/Facade.php:242
  Stack trace:
  #0 /var/www/html/app/Exceptions/Handler.php(48): Illuminate\Support\Facades\Facade::__callStatic('check', Array)
  #1 /var/www/html/vendor/laravel/framework/src/Illuminate/Foundation/Console/Kernel.php(376): App\Exceptions\Handler-&gt;report(Object(Symfony\Component\Debug\Exception\FatalThrowableError))
  #2 /var/www/html/vendor/laravel/framework/src/Illuminate/Foundation/Console/Kernel.php(141): Illuminate\Foundation\Console\Kernel-&gt;reportException(Object(Symfony\Component\Debug\Exception\FatalThrowableError))
  #3 /var/www/html/artisan(37): Illuminate\Foundation\Console\Kernel-&gt;handle(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
  #4 {main}
    thrown in /var/www/html/vendor/laravel/framework/src/Illuminate/Support/Facades/Facade.php on line 242
  
  Fatal error: Uncaught RuntimeException: A facade root has not been set. in /var/www/html/vendor/laravel/framework/src/Illuminate/Support/Facades/Facade.php:242
  Stack trace:
  #0 /var/www/html/app/Exceptions/Handler.php(48): Illuminate\Support\Facades\Facade::__callStatic('check', Array)
  #1 /var/www/html/vendor/laravel/framework/src/Illuminate/Foundation/Console/Kernel.php(376): App\Exceptions\Handler-&gt;report(Object(Symfony\Component\Debug\Exception\FatalThrowableError))
  #2 /var/www/html/vendor/laravel/framework/src/Illuminate/Foundation/Console/Kernel.php(141): Illuminate\Foundation\Console\Kernel-&gt;reportException(Object(Symfony\Component\Debug\Exception\FatalThrowableError))
  #3 /var/www/html/artisan(37): Illuminate\Foundation\Console\Kernel-&gt;handle(Object(Symfony\Component\Console\Input\ArgvInput), Object(Symfony\Component\Console\Output\ConsoleOutput))
  #4 {main}
    thrown in /var/www/html/vendor/laravel/framework/src/Illuminate/Support/Facades/Facade.php on line 242 
  </code></pre>
  
  <p>I have taken a new laravel 6 file <strong>config\app.php</strong> and a new <strong>.env</strong>
  But always this error...</p>
  
  <p>How can I solve it?</p>