如果我使用INITAMT执行一个等于循环付款金额的请求，它就会工作。
但是如果我尝试对不同的INITAMT(因此不同的TAX)计费，我得到这个错误:
Tax calculation mismatch. The tax amount for the regular non-trial billing period is different than the sum of the tax for each item in the cart.
我的实际请求:
我有4.84欧元的首付款，包括0.84欧元的增值税。
下个月的账单金额应为25.09欧元(包括6.09欧元的增值税)。
我发送的请求基本上是这样的:Method: CreateRecurringPaymentsProfile
"CURRENCYCODE":"EUR",
"INITAMT":4.84,
"TAXAMT":0.84,
"DESC":"Subscription",
"BILLINGPERIOD":"Month",
"BILLINGFREQUENCY":1,
"AMT":29,
"L_PAYMENTREQUEST_0_ITEMCATEGORY0":"Digital",
"L_PAYMENTREQUEST_0_NAME0":"Subscription",
"L_PAYMENTREQUEST_0_AMT0":29,
"L_PAYMENTREQUEST_0_TAXAMT0":6.09,
"L_PAYMENTREQUEST_0_QTY0":1
"PROFILEREFERENCE":"51a1f8f4732baf580a000031",
"PAYMENTREQUEST_0_INVNUM":"51a1f8f4732baf580a000031",
"INVNUM":"51a1f8f4732baf580a000031",
"PROFILESTARTDATE":"2013-06-26T11:59:12+0000",
和响应:
"TIMESTAMP":"2013-05-27T10:55:46Z",
"CORRELATIONID":"969d07e2cef8a",
"ACK":"Failure",
"VERSION":"74",
"BUILD":"5908853",
"L_ERRORCODE0":"10004",
"L_SHORTMESSAGE0":"Tax calculation mismatch.",
"L_LONGMESSAGE0":"Tax calculation mismatch. The tax amount for the regular non-trial billing period is different than the sum of the tax for each item in the cart.",
"L_SEVERITYCODE0":"Error"
我想用INITAMT值来做这件事，这样用户就可以在Paypal私人区域看到两个购买是相关的(即:订阅与初始支付)。
否则我将不得不为初始付款做一个单独的DoExpressCheckout。
问题是你不能(我相信)为初始金额设定一个税额。
TAXAMT是针对经常性付款的，而不是针对初始金额的。
你的对账单上写着"29欧元的账单和0.84欧元的税"。
但是你的物品清单上写着应该是6.09欧元
把你的TAXAMT改成6.09€，应该没问题。