A problem with the servers there says Coming soon in the official version 1.17

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

Unfortunately we don't accept issues related to External Servers here on the bug tracker, but please add more details if you think this also affects multiplayer over Realms, LAN, or XBL.

I'd suggest contacting the server owner directly or seeking help on the Minecraft forums.

In general, when a new release is available you may have to wait for servers to update.

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