This is an easy mistake to make. Probably we could solve this forever with better text on the page (like maybe calling the password "invite code") I've created this issue:

https://github.com/kestasjk/webDiplomacy/issues/295

Thanks!

If it's an anonymous game, I assume one of the people in the game would have to reach out to find a sub, so that they can communicate the game password. Otherwise you could probably talk to the mods about it.

How could I join this game? I do not know the password or the game creator.

You need to enter the game's password. It was set by the creator of the game.

I'm a new user. I attempted to join a game in progress (replacing an abandoned position). When asked for a password, I entered my user password, but was told it was wrong. I have changed the password, signed out and then in - no success.