Friend and I cannot join each other's Minecraft world

Hi ny name is Bella. Do you think by an chance the two of you are using different versions of the game? As mention above, the insider program has a version that is different from the store. If that isnt an issue make sure you and your friends setting
allow friends to join. The update might have reset some your setting. My last piece of advice is to unplug your xbox and router for 60 seconds. Somethimes this tend to clear up the problem. Let me know if any of my soultions worked.

I was about to say, if the error you are receiving is that there is an "outdated server" then someone is running the beta client version through the Xbox Insider app. Either both of you need to be running that version or neither one of you. It will lock
you out of worlds created or played on with that version when left until the next update or until you rejoin.

If that's not the case: exit the game fully, try to clear the local game caches, and then restart your console. Maybe restart your internet router and just give it some time.

Also check for Xbox Live service outages and Minecraft server service outages on both of their respective official websites.

you or one of you friends might have a beta version of Minecraft. if so leave the Insider program for the Beta version of Minecraft and then you might be able to play together. in the Insider hub app on xbox

Same here. The friends tab in Minecraft xbox changes the number underneath it as my LAN friends enter their world on their devices, so xbox is definitely recognising that they are there. I see that number change within seconds of them starting on their
device. But underneath that, it still says "your friends are not playing Minecraft right now" when they quite clearly are. My friends on other devices see each others joinable worlds, but I cant see those same worlds from my xbox. They can see my xbox worlds
and join, but i cannot see theirs. Help!

Is it possible that one of you or your friends has joined the Minecraft Beta Insider program?

If so, you probably have different versions of the game, and only players with the same Minecraft version can join each other's worlds.

Check that you all have either the official Minecraft version of 1.11.4. If one (or more) have the current Beta version of 1.13.something, then you can't join each other's worlds.