Dear Ruchika Sahu,
If you have an purchasing document with special procurement (for example, subcontracting or consignment), you must have entered the corresponding special procurement key in the material master(MRP2 view, field Special procurement).
This is the prerequisites for automatic source determination in the requirements planning and BOM
explosion.
You can check SAP note 206684 for more information.
Best Regards,
ian Wong Loke Foong