Assassin's Creed 2 Save file keeps getting deleted

I have the same issue. I just bought the game and had played for about an hour. There are power outages in my area, and the power went out while I was just past the mission where they imprison the father. I thought my game would have saved since I had already completed the mission. When I restarted the game after the power came back, it said "Damaged save file" and I was forced to start a new game. I'm hoping it doesn't happen again.

I have just recently experienced the same problem as you have. I was playing for roughly 5-6 hours at the point where you kill Veire( I think that’s his name). Then my screen popped up with the same thing yours did about it not being able to save. I went to make lunch, and when I came back my save vanished. This has happened to me about 3 times now and I am pissed. I really want to play the game but I’m reluctant to because of this. FYI I’ve tried resetting my Xbox One, didn’t work. I even tried uninstalling and reinstalling the game, didn’t work.

In this case, our suggestion here, attempt a Soft Factory Rest Xbox Support by selecting the following:
Reset and keep my games & apps. You should use this option as your primary choice when troubleshooting. It will reset the OS and delete all potentially corrupted data without deleting your games or apps.

OK, but some of my game saves are over one GB, like Assassin's Creed. For Assassin's Creed 2 alone, I think my save file is 1.6 GB or something like that.

Also, when I transferred my memory from one hard drive to the larger one, it told me that if i wanted to play the games I downloaded, I would have to transfer the licenses, so I did it.

I perferred Assassins creed over Skyrim maybe cause my Skyrim save got deleted somehow =(