Fatal error: Uncaught Error: Class 'Illuminate\Mail\Mailable' not found in /opt/lampp/htdocs/us/vendor/iwasherefirst2/laravel-multimail/tests/Integration/TestMail.php:7 Stack trace: #0 {main} thrown in /opt/lampp/htdocs/us/vendor/iwasherefirst2/laravel-multimail/tests/Integration/TestMail.php on line 7