当我尝试执行使用来宾流程完成的已批准PayPal付款时，而不是登录现有的PayPal帐户（工作正常）。收到错误INSTRUMENT_DECLINED。
我使用过多张支付卡，他们都有足够的资金。登录到PayPal帐户时使用的相同功能也不起作用，但连接到PayPal帐户时工作正常。
完整回复如下：
[18-08-2017 11:44:53] PayPal\Core\PayPalHttpConnection : INFO: POST https://api.paypal.com/v1/payments/payment/PAY-XXXXX/execute
[18-08-2017 11:44:56] PayPal\Core\PayPalHttpConnection : INFO: Response Status : 400
[18-08-2017 11:44:56] PayPal\Core\PayPalHttpConnection : ERROR: Got Http response code 400 when accessing https://api.paypal.com/v1/payments/payment/PAY-XXXXX/execute. {"name":"INSTRUMENT_DECLINED","details":[],"message":"The instrument presented was either declined by the processor or bank, or it can't be used for this payment.","information_link":"https://developer.paypal.com/docs/api/payments/#errors","debug_id":"XXXX"}
PayPal帐户响应：
[18-08-2017 12:45:27] PayPal\Core\PayPalHttpConnection : INFO: Response Status : 200
[18-08-2017 12:45:27] PayPal\Core\PayPalHttpConnection : INFO: POST https://api.paypal.com/v1/payments/payment/PAY-XXXX/execute
沙盒响应：
[18-08-2017 01:24:17] PayPal\Core\PayPalHttpConnection : INFO: Response Status : 200
[18-08-2017 01:24:17] PayPal\Core\PayPalHttpConnection : INFO: POST https://api.sandbox.paypal.com/v1/payments/payment/PAY-XXXX/execute
似乎客人结账需要一些配置来启用访客结账，这与现场API密钥相关联，或者与此相关。我到处检查过，但是找不到任何会产生任何影响的东西。
我也在使用PHP SDK。不确定这是否是原因，或者它中涉及的内容会导致这种情况。
非常感谢任何帮助。
谢谢！