Dear Meghna ,
Kindly check with MM or WM team whether any default storage location is there at the time of PO creation or GR (MIGO) , so that based on the Inventory stock posting this stock will be dispatched from the specific storage location and it will trigger at the time of delivery .
check the below link it will helpful to you
http://scn/.sap.com/therad/1833137.
Regards,
C.B Reddy