Fatal error: Uncaught Error: Interface "Symfony\Component\HttpFoundation\Session\SessionBagInterface" not found in /var/www/html/usophy/vendor/symfony/http-foundation/Session/Flash/FlashBagInterface.php:21 Stack trace: #0 {main} thrown in /var/www/html/usophy/vendor/symfony/http-foundation/Session/Flash/FlashBagInterface.php on line 21