I can’t seem to change my country/region

I want to join family sharing of a group of members but apple tells me since I don’t have the same country/region with them(UK), I cant join. So every time I try to change my country/region in Apple ID it tells me ‘You cannot change the store front information for your account at this time’

and I’m confused at this point on what to do. I also cancelled all my subscriptions. It’s been bugging me for days and I can’t download any app because of it and all my music is gone. Please if you’ve encountered such or you have a solution help me, please.