about pop up in standard transaction

hello everyone,

I need help in one standard transaction.In migo transaction after inserting excise invoice i am getting error " Excise invocie XXXX for the vendor xxxxx exits.

It means systme is checking if a same excise invoice no is entered for same vendor again. Likewise we need to have a check / control on Delivery note i.e. if same delivery note no is entered twice for same vendor system should give a warning / erro message like excise inv check.

Plz suggest some solution.