Fatal error: Uncaught Error: Interface 'GuzzleHttp\ClientInterface' not found in C:\inetpub\wwwroot\mantis\vendor\guzzlehttp\guzzle\src\Client.php:26 Stack trace: #0 {main} thrown in C:\inetpub\wwwroot\mantis\vendor\guzzlehttp\guzzle\src\Client.php on line 26