Hello.

Yes, you can. You can freeze your seat in any of the rounds if you are OK with the choice that you get. But be sure before freezing your seat as you will not be able to change it afterwards. There is always a chance that you will get something better in the next round. But after freezing your seat, there is no chance that you will get something better. But if you think that whatever you got in your 3rd(or whatever round you want to freeze your seat after) is good and that’s what you wanted all the time, then you must freeze your seat as there is a possibility that your choice that you will get might change in the next round.

Hope this is helpful.

Good luck.