Update an existing Receipt number in Oracle 12.X version

Hello All,

We have a situation where an external system is integrated with Oracle for Purchase Receipts. Due to an integration issue very few receipts have failed saying "Error: Receipt number must be unique". Upon investigating, we identified that old receipt# (lets say 123) was tied incorrectly to a PO. Is there a way to update a such Receipt numbers to a different number to an already existing PO?

PS: PO or line is closed, Invoice has been paid and GL books are reconciled.

Thank you very much in advance.