Unable to Cancel AP Invoice(I Supplier Portal) using Rest API.

Summary:

Hi All,

Our business receives a lot of invoices thru Supplier Portal, and some of them are rejected in the approval process. However, if the rejected invoices are not cancelled, the PO line used in the invoice cannot be reused by the supplier to create another invoice.. So, we either want the PO line to be released when an invoice is rejected....or an automatic way to cancel all rejected invoices

When a business user rejects an invoice submitted to them through I Supplier portal, it goes back to the supplier in ‘Rejected’ status.

Now we are trying to Cancel the Rejected invoices via Rest API to avoid the manual.