Fatal error: Uncaught Error: Interface "Billow\Contracts\PaymentProcessor" not found in /home2/celtixg1/public_html/script/vendor/billowapp/payfast/src/Payfast.php:9 Stack trace: #0 {main} thrown in /home2/celtixg1/public_html/script/vendor/billowapp/payfast/src/Payfast.php on line 9