Received error: 400 Raw response:{"name":"VALIDATION_ERROR","details":[{"field":"transactions[0].amount","issue":"Amount cannot be zero"},{"field":"transactions[0].item_list.items[0].quantity","issue":"Required field missing"},{"field":"transactions[0].item_list.shipping_address.country_code","issue":"Must not be blank"},{"field":"transactions[0].item_list.items[0].price","issue":"Required field missing"},{"field":"transactions[0].item_list.shipping_address.country_code","issue":"Country code must be 2-character ISO 3166-1 value (upper case)"}],"message":"Invalid request - see details","information_link":"https://developer.paypal.com/docs/api/payments/v1/#error-VALIDATION_ERROR","debug_id":"d9ef016f6b6df"}