Lost all achievements (Rocket League)

Usually we play together, but somehow I decided to connect 3 gamepads for three players. After that, when we start playing together, the second player is now with zero statistics and a newbie, the car is standard. How to return the second player to his car and achievements?
Now, after the update with new stadiums, it turned out that all achievements were lost in both players, but the rating remained. Constantly gives to play against amateurs and pros, and in competitions in general there is a complete zero. How do I get achievements back for players?