MIGO error message

Hi all,

Have a reqt to change material number in Line item data in MIGO Transaction.

While attempting to do that through BADI, I am able to change it in the structure but its not getting displayed on screen. Getting system message as:

BADI: Field MATNR is not ready for input. (Change is not taken over)

Message no. MIGO050

Diagnosis

The contents of field MATNR have been changed in BAdI MB_MIGO_BADI (method LINE_MODIFY). The field, however, is not ready for input, so the change cannot be copied.

Can somebody help. where can we find MIGO messages?

Thanks,

cs