Country code is determined by your ip-adress, there is no way for you to manually change it, unless you download a vpn witch you can set to a specific country (not all vpn's can do this, you might have to pay to get it)
If your country code is currently in the wrong country then there is a chance that it will change back some day, it gets updated regulary, and sometimes it fixes itself. But there is a big chance that you will keep this country code for quite a while.
An admin can manualy change your country code but as it will change back to your current one there isn't much use in doing it.