Our accounts payable person is asking how to resolve an issue that should be simple, but I'm not sure how to resolve it.

In simplistic form, we entered an invoice for $10.00.   We paid $11.00.    Sage won't let us enter a payment of 11.00. 

How do I pay the 11.00 so that it shows up correctly on the GL side, and also show the 1.00 credit in AP?

Thanks.