God Eater 2

[LunaMoo]

Never happened to me, but I also never depended on an auto save:].
If you used any cheats, you can try disabling them since many of cheats for this game could easily break it when abused, however if your game actually messed up saving and don't have any backup save or a savestate, I'm affraid that there's nothing you can do to recover it. If you at least have a savestate, you can just load it and save the game normally.