Fatal error: Uncaught Error: Class 'Symfony\Component\Config\Definition\Exception\InvalidConfigurationException' not found in C:\xampp\htdocs\plugins\Symfony\Component\Config\Definition\Exception\DuplicateKeyException.php:20 Stack trace: #0 {main} thrown in C:\xampp\htdocs\plugins\Symfony\Component\Config\Definition\Exception\DuplicateKeyException.php on line 20