使用PayPal Refund API进行自适应付款的部分退款返回内部错误(520002)

我正在尝试编写代码来为自适应支付做部分退款.

我读过https://developer.paypal.com/docs/classic/api/adaptive-payments/Refund_API_Operation/

这就是我的要求

curl -s --insecure
-H "X-PAYPAL-SECURITY-USERID: api_username" 
-H "X-PAYPAL-SECURITY-PASSWORD: api_password" 
-H "X-PAYPAL-SECURITY-SIGNATURE: api_signature" 
-H "X-PAYPAL-REQUEST-DATA-FORMAT: NV" 
-H "X-PAYPAL-RESPONSE-DATA-FORMAT: NV"
-H "X-PAYPAL-APPLICATION-ID: your_app_id "          
https://svcs.sandbox.paypal.com/AdaptivePayments/Refund  -d  
"requestEnvelope.errorLanguage=en_US 
&requestEnvelope.detailLevel=ReturnAll
&transactionId=xxxxxxxxxx
¤cyCode=USD
&receiverList.receiver(0).amount=10.00"

原始交易金额> 10.00,我试图部分退还这笔款项

响应基本上是"内部错误",错误代码为520002

有任何想法吗？