Question

I’m trying to add TAXAMT to the transaction. Here’s what the query sent:

&PAYMENTREQUEST_0_PAYMENTACTION=Authorization
&RETURNURL=http://zzz.com/returnurl
&CANCELURL=http://zzz.com/cancelurl
&NOSHIPPING=1
&PAYMENTREQUEST_0_CURRENCYCODE=USD
&L_PAYMENTREQUEST_0_QTY0=1
&L_PAYMENTREQUEST_0_NAME0=Shirt
&L_PAYMENTREQUEST_0_AMT0=89.10
&L_PAYMENTREQUEST_0_TAXAMT0=3.56
&PAYMENTREQUEST_0_TAXAMT=3.56
&PAYMENTREQUEST_0_AMT=92.66

but for some reason it’s not working. When I add the TAXAMT as a normal item it goes through:

&PAYMENTREQUEST_0_PAYMENTACTION=Authorization
&RETURNURL=http://zzz.com/returnurl
&CANCELURL=http://zzz.com/cancelurl
&NOSHIPPING=1
&PAYMENTREQUEST_0_CURRENCYCODE=USD
&L_PAYMENTREQUEST_0_QTY0=1
&L_PAYMENTREQUEST_0_NAME0=Shirt
&L_PAYMENTREQUEST_0_AMT0=89.10
&L_PAYMENTREQUEST_0_QTY1=1
&L_PAYMENTREQUEST_0_NAME1=Sales+Tax
&L_PAYMENTREQUEST_0_AMT1=3.56
&PAYMENTREQUEST_0_AMT=92.66

Can anyone help me figure out the problem with the TAXAMT. At the moment I get the following error with it:

SetExpressCheckout API call failed.
Detailed Error Message: The totals of the cart item amounts do not match order amounts.
Short Error Message: Transaction refused because of an invalid argument. See    additional error messages for details.
Error Code: 10413
Error Severity Code: Error

Answer 1

You’re missing:
&PAYMENTREQUEST_0_ITEMAMT=89.10

L_PAYMENTREQUEST_xxxxx indicates the amounts for individual items.
PAYMENTRQUEST_xxxx indicates the total amounts for all items together.