first of all let me tell you whats happenning presently with the system:
on changing the final invoice flag in PO,the output types ZNE3 is detemined by nace config which results in creation of the idoc which are finally used to send across the other system.
So,the requirement is whenever the final invoice flag in a PO is changed,the idoc should not get created at all.
i know,our goal is stop the entries to be created in NAST table since that only detemines the idoc types processing later.
Please give me suggestions on how to proceed on this?