How did you update the game?
If you use itch app then you can try to delete and re-install the game. Either way just follow the instructions that relate to you from the topic https://rinmarugames.itch.io/oathbreaker-season-2/devlog/164639/chapter-1-of-the-public-version-is-released. I think if you successfully re-install the game (or re-place the old files with new ones) there should be no problem.