In the current release, the steam-cloud autosave system is connected.
We recommend that you back up your saves - copy the folder Cache > C:\Users[Username]\AppData\LocalLow\CarX Technologies\Drift Racing Online\Cache to a separate location.
Make sure the checkbox "Enable save sync with Steam Cloud" is checked in the game settings in Steam.
Update 2.13.4
Source: Steam Community (opens in a new tab)