We have the following scenario which we don't know how to handle from an AP perspective.  We issued a purchase order to vendor A.  Vendor A delivered the goods and submitted a partial invoice which was paid.  Meanwhile vendor A sold its division (along with the debt) to vendor B and now vendor B submitted an invoice against the purchase order.  What's the process to allow payment to Vendor B for a PO that was originally setup for Vendor A (and for which Vendor A has been partially paid)?  

Thanks