Thanks for posting in the Community.
If you're using a Premium account, it won't be possible to change the country settings manually. This will happen automatically on the next payment date if you've updated your payment method to a one issued in the country you're currently residing in.
If you're using a free account and still can't change the settings, it's worth trying to do this through a different device, preferably a desktop PC connected to the internet through a LAN-cable. You can also try using an incognito browser window for that.
Keep us posted,
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