I bought the Yearly Pass using my UK address......no problems
Try flushing out your browser cache and history.....you may still have some UK cookies in there (in firefox it's under the "menu" button, three horizontal bars, top right) OPTIONS, PRIVACY AND SECURITY, scroll down to CACHED WEB CONTENT .........also, you need "settings" to INCLUDE all your details (menu, options, privacy and security) ie remember TICK ...., remember TICK....., accept cookies TICK.......if you try to un-tick any of these boxes and "hide" your identity, then iFollow assume you are deliberately hiding your location and are actually in the UK......also you cannot use a VPN or a Private Browsing window.
I occasionally get "kicked off" at half-time with an error message "your membership is in use in a different location"......I flush out the Cache and it works fine