Fatal error: Uncaught Error: Class 'Symfony\Component\Form\AbstractExtension' not found in C:\Apache24\htdocs\InvoiceTracking\vendor\symfony\form\Extension\Validator\ValidatorExtension.php:27 Stack trace: #0 {main} thrown in C:\Apache24\htdocs\InvoiceTracking\vendor\symfony\form\Extension\Validator\ValidatorExtension.php on line 27