Fatal error: Uncaught Error: Interface 'GuzzleHttp\ClientInterface' not found in /var/www/support-dev.maxperutzlabs.ac.at/api/vendor/guzzlehttp/guzzle/src/Client.php:17 Stack trace: #0 {main} thrown in /var/www/support-dev.maxperutzlabs.ac.at/api/vendor/guzzlehttp/guzzle/src/Client.php on line 17