You are only supposed to use the store in the country where you live. You may not be able to change until your subscription runs out.
You need a zero account balance, you need to cancel all your subscriptions, you need a credit card issued by a bank in the country the store is in, and you need a billing address in that country.
Purchases - View, change, or cancel your subscriptions
Purchases - Subscriptions not billed through Apple
Region - Change your iTunes Store, iBooks Store, or App Store country or region
If necessary, contact iTunes Support. Either use the form or scroll to the bottom of the page in the 2nd link. Follow through the screens to get a chat or telephone option.