In order to prevent problems with mismatched game versions, Dominations does not allow players on older game versions to view villages that have logged into newer versions of the game. This can happen if you're using two separate devices to play the game and only one has updated to the latest version. This can also happen when attempting to visit another player's village. Multiplayer matchmaking automatically filters opponents to prevent this from being an issue, but it’s possible for World War to pull players from mismatched versions into the same war.
The solution for this is to update to the latest version of the game and gain access to all villages; however, it can take a few hours for the update to become available to all players. If you’re seeing this error, check for an update to your game version. If one is not yet available, keep checking back and within a few hours, the update should become available to you.