Fatal error: Uncaught Error: Class 'Symfony\Component\String\AbstractUnicodeString' not found in /var/www/html/test-project/my-app/vendor/symfony/string/UnicodeString.php:33 Stack trace: #0 {main} thrown in /var/www/html/test-project/my-app/vendor/symfony/string/UnicodeString.php on line 33