Can’t change country

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.  You may need to pick a problem that is slightly different than yours to get a chat option.  

iTunes Support

iTunes Support – world wide

Do you have access to another WiFi network where you can try? That has worked for several people.

Try a restart.

Restart your iPhone, iPad, or iPod touch

Try a forced restart.

Reset Device

You are welcome.

Hi, I did the same but then updating the country/region settings from browser isn't reflecting on device. Seems some technical problem which started in last day or two.

Even I am facing the same issue and I have tried doing it on my mac and on my iPhone still no luck as its showing blank white page everywhere. I tried restarting my devices and still its same.

I changed my country by signing in online through apple website. So you can try using this method and hopefully it will help you.

Thanks Eric for the help.