Fatal error: Uncaught Error: Interface "PayPal\Handler\IPayPalHandler" not found in /home/rwebserver/public_html/quanta/vendor/paypal/rest-api-sdk-php/lib/PayPal/Handler/RestHandler.php:20 Stack trace: #0 {main} thrown in /home/rwebserver/public_html/quanta/vendor/paypal/rest-api-sdk-php/lib/PayPal/Handler/RestHandler.php on line 20