Hi Hari,
T.Code: F.13 itself automatic clearing not manual clearing.
GR/IR Clearing is a month end activity, based on Dr & Cr matching criteria system automatically clear line items by executing T.Code: F.13.
Insted of executing this screen manually create job for the program (SAPF124) then every month system will process GR/IR auto clearing.
Regards,
Viswa.S