If you're trying to change the location or the flag on a player profile, the first thing you need to do is make sure you have claimed the player profile. If you have already claimed your player profile, go to the profile you have claimed. It should look like the screen below. Click 'Edit profile'.
Once you are in the edit profile page, as in the below photo, you will be able to change the residence which shows up as the location on the player profile. You will have to change the nationality at the same time, which shows up as the flag on the player profile.
You will then see the new place of residence on the player profile and the flag. If you find that you still don't see the city listed or the flag, please reach out to us.