Fatal error: Uncaught Error: Class 'Symfony\Component\DependencyInjection\Argument\IteratorArgument' not found in /home/devmecseminars/public_html/mec/vendor/symfony/dependency-injection/Argument/TaggedIteratorArgument.php:19 Stack trace: #0 {main} thrown in /home/devmecseminars/public_html/mec/vendor/symfony/dependency-injection/Argument/TaggedIteratorArgument.php on line 19