Cannot connect to a friend's realm. Gives message "You're not invited to play on this server"

Cannot connect to a friend's realm. Gives message "You're not invited to play on this server", this is despite having been a member of the realm for some time. 

I have tried leaving the realm and successfully accepting a new invitation. Other people are joining the realm without issue. They also report that when they are in realm I am being listed as in the realm even though I am not. (This was still the case when I had left the realm)

I have logging in and out and reinstalling the game. I am also definitely not online in a different location.

This problem began after I accidentally pressed cancel when joining the realm.

I have no problems joining other servers.

Thanks for your attention.