Have you downloaded the game from from a different source than Play Store?
The few dozen times I have been reported this, it is always because of a cheated/modified version of the game.
No, but I did do some cleaning on my LG (rooted). I know that the save file opened while I had it in the downloads folder. It probably got edited and saved while in my pocket. The LG device is also pretty old and I only have 850 MB memory space for the 1 GB RAM. Only 400 MB is free to play the game though. Probably has to do with the frequent crashes I get.