We get this error every time an update happens. We play the offline version lan. Is there a way to fix this besides having to reinstall the game over and over and over each time? We get to play for a bit, but the very next day database mismatch. We do not use mods.

Updates aren't happening that often so if you're getting it the next day something else is wrong. v1.1.9.7 went live on the 6th December so if you're on that you should be fine.