[Minecraft Xbox One BETA BUG!] ,,XBL Account Required''

[Minecraft Xbox One BETA BUG!]
I can't go on Servers anymore!
I can't Join or invite my friends to maps!
Evrytime i try to go on the Mineplex Server i get ,,XBL Account Required'' error!
I tryd it with a secound acc but same error!
All my friends can play without a problem!
I seen some guys on the Internet that have the same problem but no one knows what do to now!

PLEASE HELP