Fatal error: Uncaught Error: Class 'Nexmo\Client\Callback\Callback' not found in /home2/circuitos/public_html/circuitos-dev/vendor/nexmo/client-core/src/Message/Callback/Receipt.php:12 Stack trace: #0 {main} thrown in /home2/circuitos/public_html/circuitos-dev/vendor/nexmo/client-core/src/Message/Callback/Receipt.php on line 12