Change Apple ID Country
Hi,
Until today, Apple Store was not available in Serbia. In order to be able to purchase storage on iCloud and other things, I have registered my Apple ID to Croatia, long time ago. I have also registered a Family Sharing, and there is also a child iPhone linked via parental control to my iPhone. Altogether there are three adult, one child and a Mac on the Family Sharing.
As of today, Apple Store is officially available in Serbia. I have started changing the Country/Region on all of the phones and the Mac. However, I am not entirely able to change the account country:
What I'm supposed to do in order to completely change Country/Region on all iPhones and the Mac?