Correcting Quantity-based PO Matched Invoice that has already been paid

Summary:

We currently have an PO Matched invoice that has already been paid several months ago.

However, we have noticed that the PO still have an Open Invoice Amount despite the quantity being fully consumed.

(The amount was manually changed while the quantity remained the same)

We are aware that there is a method to correct the invoice quantity by creating a new correction invoice and indicating a negative quantity.

This is currently not possible as the quantity we have for the line is only 1. It is not possible for us to indicate -0.75, for example.

Is there a way for us to address the quantity on the invoice line(the invoice is matched to multiple PO lines) without the need to void the payment and redoing this all over again?