How to cancel invoice or lines that have a PO with a cancelled line or 0 amount quantity?

We enabled a functionality (Prevent Cancellation of Partially Received or Invoiced PO's) in mid January. Before we enabled this feature we had two purchase orders and their respective invoices that had a line cancelled on the PO and had 0 amount quantity lines. The invoices were created before the lines were cancelled or edited to 0 amounts. When trying to cancel the lines or cancel the invoices, the system will not allow it and will display: "The invoice in its current state will not allow..."