Fatal error: Uncaught TypeError: sizeof(): Argument #1 ($value) must be of type Countable|array, string given in /var/www/html/install/vendor/paypal/rest-api-sdk-php/lib/PayPal/Common/PayPalModel.php:176 Stack trace: #0 /var/www/html/install/vendor/paypal/rest-api-sdk-php/lib/PayPal/Common/PayPalModel.php(176): sizeof('T-Shirt of the ...') #1 /var/www/html/install/vendor/paypal/rest-api-sdk-php/lib/PayPal/Common/PayPalModel.php(278): PayPal\Common\PayPalModel->_convertToArray(Array) #2 /var/www/html/install/vendor/paypal/rest-api-sdk-php/lib/PayPal/Common/PayPalModel.php(293): PayPal\Common\PayPalModel->toArray() #3 /var/www/html/install/vendor/paypal/rest-api-sdk-php/lib/PayPal/Api/Plan.php(355): PayPal\Common\PayPalModel->toJSON() #4 /var/www/html/install/vendor/paypal/rest-api-sdk-php/sample/billing/CreatePlan.php(66): PayPal\Api\Plan->create(Object(PayPal\Rest\ApiContext)) #5 /var/www/html/install/vendor/paypal/rest-api-sdk-php/sample/billing/UpdatePlan.php(14): require('/var/www/html/i...') #6 /var/www/html/install/vendor/paypal/rest-api-sdk-php/sample/billing/CreateBillingAgreementWithCreditCard.php(12): require('/var/www/html/i...') #7 {main} thrown in /var/www/html/install/vendor/paypal/rest-api-sdk-php/lib/PayPal/Common/PayPalModel.php on line 176