Fatal error: Uncaught Error: Class 'Doctrine\DBAL\Event\SchemaEventArgs' not found in C:\xampp\htdocs\dpbb\vendor\doctrine\dbal\src\Event\SchemaAlterTableAddColumnEventArgs.php:17 Stack trace: #0 {main} thrown in C:\xampp\htdocs\dpbb\vendor\doctrine\dbal\src\Event\SchemaAlterTableAddColumnEventArgs.php on line 17