There is a possibility of your Operating System deleting the game save data since it is saved locally and not in cloud or by using an account so far. The savedata folder is in C:\ProgramData\InterAction studios\CIU\30 ( Number 30 since this is the latest version ), as being told by the user @VerMishelb in the FAQ:
I’ve done some tests and if you delete the numeric folder thus starting a new account, and then replace the files with your back-up save data, it will still give you the new account. The only way to get your old account data would be to delete the entire folder then put the back-up folder there, not replacing the old files.
Anyway, in your case, the game-reset is most likely done by either a program, a virus a windows bug or just something simple that might slip my mind.
I would suggest this:
- Starting the game with the savedata folder open ( In case you can’t find the
ProgramDatafolder, just type%programdata%up there, where the location is specified) - Start the game, and if you have 0 progress again, try to do a mission just so you don’t have 0 score. Then copy that folder somewhere and start the game again.
2a) Is the progress lost again? If so, delete theCIU\30folder and instead put the folder that you copied before in there.
2b) Is the progress still there? Shut down your PC then start it again and verify if the progress is still there. If not, delete theCIU\30folder and instead put the folder that you copied before in there.