Exit program check batch in Process Order

Hi Expert,

I have already 1 exit program for check batch in process order.

While the exit program is running release process order.

Program show error message if does not input number of batch or error message when exit program detect duplicate of batch in another process order.

If once of process order released with batch ext.123456 and I want to cancel this process order.

In new process order might to use batch number is 123456 but exit program detect of condition is REL status and 123456 of batch.

Question

How i can to do this if i want to create new process order and use batch no. 123456.

and

Old process order cancelled, might can not revork to REL status.

Thank you very much.