Unable to connect to friend's worlds :(

I have been trying to play Minecraft with my friend for the past half hour, but we haven't been able to join each other's worlds. I played Minecraft with a couple of my other friends this morning and the game worked just fine. I've tried joining my friend on console edition on my Xbox 1 and Xbox 1X and also pocket edition, and it still didn't work. My friend and I have tried turning our WiFi off and on again, checking for updates, and joining through invites; nothing has worked. The issue seems to only happen with this particular friend, and I don't know why. Please fix this issue soon!!!