Unable to connect to store problem!

Basically whenever I try to buy coins or connect to realms I get a pop up message saying unable to connect to store and please check your internet connect. So I checked my internet and it was completely fine so I'm just a little bit confuse about the situation and if anyone has an answer it would be great if they could get back to me a soon as possible.

Sincerely,
Eoin O'Reilly