Fatal error: Uncaught Error: Interface "Nexmo\Client\Callback\CallbackInterface" not found in /home/trombino/public_html/africa.trombino.org/vendor/nexmo/client-core/src/Client/Callback/Callback.php:12 Stack trace: #0 {main} thrown in /home/trombino/public_html/africa.trombino.org/vendor/nexmo/client-core/src/Client/Callback/Callback.php on line 12