It kicks my friend out of his world when i try load and make him restart

Does it say, "You were kicked from the game" and you rejoin and it says "You are not invited to play on this server?"

Thank you for your report!
However, this issue is Invalid.

When everyone gets disconnected it means that the server has crashed. Crashes such as these are logged automatically, this will therefore be investigated further by the development team internally.

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