AppStore caught in loop

When I open the AppStore on the iPad I get caught in a loop where it's telling me 'the item is unavailable' and 'iTunes store is not available'. I haven't attempted to do anything, and I can't do anything on the store as it all remains grey, except when it tries to contact the store it just brings up the two dialog boxes. The last item I bought was Dungeon Village Story last night, and that purchase was fine.

Any thoughts?

 

I did the obvious and signed out and back in, I say obvious, but I had to do it through the Settings app which wasn't so obvious. I've never had problems with it until this point.