When trying to join my friends multiplayer world, I haven't been able to join and receiving an "unable to connect to world" screen. I have tried using a vpn, un-adding then re-adding a friend, loading up my own world, and checked that joining multiplayer worlds was on. I have also had the same problem with my iPad with the same issue with no solution.
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We're tracking this issue in MCPE-36190, so this ticket is being resolved and linked as a duplicate.
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