BAPI_RESERVATION_CREATE not picking the G/L in reservation creation

Hi All ,

Scenario is Automatic reservation is generated using BAPI_RESERVATION_CREATE   but its creating reservation without G/L although G/l code has been given in initial entry  although same entry if key in in mb21 then reservation is creating along with G/L

Query is what could be the cause that auto reservation using bapi is not picking the G/L or is there any configuration problem or any check box is missing while giving initial entries for reservation .

Appreciate your quick response .

Thanks