Fatal error: Uncaught Error: Interface "GuzzleHttp\Promise\PromiseInterface" not found in I:\www\oauth2\auth_server\vendor\guzzlehttp\promises\src\FulfilledPromise.php:11 Stack trace: #0 {main} thrown in I:\www\oauth2\auth_server\vendor\guzzlehttp\promises\src\FulfilledPromise.php on line 11