Hi Praneeth,
Once production is completed with respective to all activities like GI, Confirmations and GR then concerned production responsible personal who handles the production task does Techncial Completion of order (TECO) in system which is the source of comunication to planning and finance for further activities.
Normally production team will do the TECO once they complete the producion activity or if they feel no further work needs to be done on order.TECO on order clears the open reservations and capacities if available.Once TECO is completed FI team can do the order settlement.
Till cost balance on the order is Zero order cannot be Closed.
Thanks & Regards,
Ramagiri