Fatal error: Uncaught Error: Class "Symfony\Component\Serializer\Normalizer\AbstractNormalizer" not found in /home/wizilen/www/vendor/symfony/serializer/Normalizer/AbstractObjectNormalizer.php:51 Stack trace: #0 {main} thrown in /home/wizilen/www/vendor/symfony/serializer/Normalizer/AbstractObjectNormalizer.php on line 51