Fatal error: Uncaught Error: Class "Symfony\Component\Serializer\Normalizer\AbstractNormalizer" not found in /home/ldt/public_html/canvas/udoit/vendor/symfony/serializer/Normalizer/AbstractObjectNormalizer.php:37 Stack trace: #0 {main} thrown in /home/ldt/public_html/canvas/udoit/vendor/symfony/serializer/Normalizer/AbstractObjectNormalizer.php on line 37