Ah yikes, your save file might've gotten corrupted somehow. A few folks have run into this in the past, if you go to your AppData\Local\AtC_BB\Saved\SaveGames folder and delete your .sav file manually, it should fix the issue but unfortunately you'll have to start the game over from the beginning. It should automatically create a new save file upon booting it back up and it should function as it usually does. Lemme know if that fixes the issue for ya.