Fatal error: Uncaught Error: Class "PayPal\Rest\ApiContext" not found in D:\xampp\htdocs\SSWPOS\vendor\paypal\rest-api-sdk-php\sample\bootstrap.php:73 Stack trace: #0 D:\xampp\htdocs\SSWPOS\vendor\paypal\rest-api-sdk-php\sample\bootstrap.php(45): getApiContext('AYSq3RDGsmBLJE-...', 'EGnHDxD_qRPdaLd...') #1 D:\xampp\htdocs\SSWPOS\vendor\paypal\rest-api-sdk-php\sample\billing\GetBillingAgreement.php(8): require('D:\\xampp\\htdocs...') #2 D:\xampp\htdocs\SSWPOS\vendor\paypal\rest-api-sdk-php\sample\billing\SearchBillingTransactions.php(11): require('D:\\xampp\\htdocs...') #3 {main} thrown in D:\xampp\htdocs\SSWPOS\vendor\paypal\rest-api-sdk-php\sample\bootstrap.php on line 73