After playing for a few hours last night I saved the game and turned it off, only to open it today and see all the saves are blank. Whenever I try to start a new game and save it, it gets deleted. Is there a solution to this?

I've had the same issue. What helped me was backing up my save files from the AppData folder after a session and renaming game.sav to a longer file name that the game generates everytime I launch the game. (Something like "g00B0BD917A3091FB_game.sav"). Placing it back to the SaveData folder and opening the game, my progress was back.

It worked for a while but today I had to do this again for some reason. Seems like it's a gamble everyime I open the game. I think it has something to do with the cloud sync. I don't know, but it's getting really tiring...

I had the same issue. After I did go from the world map back to the main menu and closed the game with the back to the desktop option it seems to save without the issue.