Fatal error: Uncaught Error: Call to a member function suspend() on null in /mnt/VenusReview/review/lyrasoft/dva/master/vendor/paypal/rest-api-sdk-php/sample/billing/SuspendBillingAgreement.php:24 Stack trace: #0 {main} thrown in /mnt/VenusReview/review/lyrasoft/dva/master/vendor/paypal/rest-api-sdk-php/sample/billing/SuspendBillingAgreement.php on line 24