Multiplayer Connectivity Issues

I play Minecraft with a friend who plays on MCPE. Recently they were not able to connect to my game through xbox live because they could not see me as being online. I tried sending an invite but they would never receive it. We tried doing it the other way around where I would try to enter their world. I could've seen the world but it would stick on "Locating Server". Invites would go through but it would just keep on saying locating server. We also tried moving to the beta vrsion to see if anything happened but the same problem persisted.