International flights: counters are opened 2 hours before STD
Domestic flights: counters are opened 1 hour 30 minutes before STD
International flights: counters are closed 60 minutes before STD
Domestic flights: counters are closed 30 minutes before STD
*STD: Scheduled Time of Departure.
If you fail to check-in on time you will not be allowed to travel on the flight, which may cause your ticket invalid for travel or becoming non-refund in case there are restrictions on changes. You will need to purchase new ticket.
So, you are recommended to be at the airport at least 2 hours before departure for both domestic flights and international flights.