One friend listed on joinable friends. They are playing in their own world. I click join and it takes me to CubeCraft. My friend is not listed on the CubeCraft server.

Restarting Minecraft doesn't help.

Restarting the PC didn't help.

Joining a different server - Lifeboat - and then repeating still takes me to CubeCraft.

For a little while the CubeCraft server popped up in LAN worlds.