Fatal error: Uncaught Error: Interface "Nexmo\Entity\JsonSerializableInterface" not found in /home/gyannewsoftware/public_html/school6_EduFirm/vendor/nexmo/client-core/src/Account/Config.php:10 Stack trace: #0 {main} thrown in /home/gyannewsoftware/public_html/school6_EduFirm/vendor/nexmo/client-core/src/Account/Config.php on line 10