Seems like you've lost your gamesave.
what you can do for that is, there is several gamesaves online that you could use, or you would have to start a new one. when you format your PC you will loose all progression that you had on your account unless you made a backup of it.
Keep in mind if you want to format again at a later time, go into your ETS2 folder and save your profile! (Make a backup OF it and save it somewhere that you can download it later, or on a seperate hardrive!)
Hope that helped.