Problem in MB_MIGO_BADI, Reference Document No.(MSEG-LFBNR) field is blank

Hi All,

I have implemented the MB_MIGO_BADI. At the time of Goods Receipt a Custom tab is triggering only for a set of vendors as per my requirement. The problem is, in the Item level Ref. Docu field(MSEG-LFBNR) is blank when ever it's triggers my custom tab. But in the normal scenario Ref Docu field contains the Material Document No. at the time of Goods Receipt and at the time of Cancel it will have canceled material document no.

Please let me know what is the cos of this..

Regards,

Pavan.M