Fatal error: Uncaught Error: Interface "Symfony\Component\HttpFoundation\Session\FlashBagAwareSessionInterface" not found in C:\xampp\htdocs\adminlte3\vendor\symfony\http-foundation\Session\Session 2.php:33 Stack trace: #0 {main} thrown in C:\xampp\htdocs\adminlte3\vendor\symfony\http-foundation\Session\Session 2.php on line 33