Thai AirAsia booking website is very confusing and very unforgiving, I booked an international flight where the standard on most other airlines I flew would be at least 15 kilos. I was told you paid for 0 kilos going, but 40 kilos coming back. I had to double baggage fees for a minor error. I just want to warn other passengers of this as it seems Thai AirAsia deliberately make it hard for those extra fees. I would be looking at other airlines to fly with.