Fatal error: Uncaught Error: Class 'PayPal\Common\PayPalModel' not found in /home/ultraunlock/public_html/PayPal-PHP-SDK/lib/PayPal/Api/Cost.php:19 Stack trace: #0 {main} thrown in /home/ultraunlock/public_html/PayPal-PHP-SDK/lib/PayPal/Api/Cost.php on line 19