PO already Invoice but receipt being returned by user

Dear Oracle Guru's,

I just found out that user return a receipt that already invoiced and paid.
When I try to tested it in the development, the case can be reproduce again.
How to avoid this? Because there is no error warning show up too.
It is really dangerous because the PO can be overbilled.

Is there a setting to avoid this?
Need your help,

Thanks and Regards,
Ann