Fatal error: Uncaught Error: Class 'Symfony\Component\HttpKernel\HttpCache\AbstractSurrogate' not found in D:\xampp\htdocs\psp\backend\vendor\symfony\http-kernel\HttpCache\Ssi.php:22 Stack trace: #0 {main} thrown in D:\xampp\htdocs\psp\backend\vendor\symfony\http-kernel\HttpCache\Ssi.php on line 22