How to apply a Discount to an AP PO Matched Invoice via cXML

My Customer has 4 Suppliers where they are receiving AP PO Matched Invoices via cXML.

AMAZON, one of the Suppliers, applies discounts to the Invoice after the PO has been issued.

They will send a cXML Invoice as follows: Total Invoice Amount= (Total of Lines, Freight, Miscellaneous and Taxes) minus the Discount.

AMAZON is sending the Discount as follows for the AP Invoice and Credit Memo:

<InvoiceDetailDiscount percentageRate="5.9700">

<Money currency="USD">-191.44</Money>

</InvoiceDetailDiscount>

These fields that AMAZON is sending are not currently mapped to any fields on the cXML Message defined in Oracle Cloud.

Therefore, the Invoice will go On Hold since the Invoice Amount at the Header does not equal the Total of Lines, Freight, Miscellaneous and Taxes.