Fatal error: Uncaught Error: Interface "Symfony\Component\Config\Definition\Builder\NodeParentInterface" not found in /var/www/html/v12.hallescherfc.de/vendor/symfony/config/Definition/Builder/TreeBuilder.php:23 Stack trace: #0 {main} thrown in /var/www/html/v12.hallescherfc.de/vendor/symfony/config/Definition/Builder/TreeBuilder.php on line 23