Fatal error: Uncaught Error: Class 'Symfony\Component\HttpFoundation\Session\Attribute\AttributeBag' not found in D:\workspaces\liZiPingBack\vendor\symfony\http-foundation\Session\Attribute\NamespacedAttributeBag.php:20 Stack trace: #0 {main} thrown in D:\workspaces\liZiPingBack\vendor\symfony\http-foundation\Session\Attribute\NamespacedAttributeBag.php on line 20