Can’t contact any friends, can’t read their messages in app, cannot call them, is it only me today? Yesterday it was fine, also no mute/sanctions, what is it?
Yes I am having this issue. it keeps saying that friend is not online
thank you, same here, same for in-game chat with friends 
Yep, I never have this problem. this has only started happening today. It is a huge issue as I need to contact Bnet friends
eventually, blizzard app reboot helped me at least to join a voice conference