Fatal error: Uncaught Error: Class 'GuzzleHttp\Promise\RejectionException' not found in D:\xampp\htdocs\psp\backend\vendor\guzzlehttp\promises\src\AggregateException.php:10 Stack trace: #0 {main} thrown in D:\xampp\htdocs\psp\backend\vendor\guzzlehttp\promises\src\AggregateException.php on line 10