if you have a new account , you can link a facebook sign in through friends list on the left , click Facebook icon , or you can link a facebook account and google account by clicking on your racer ID and on right you will see a facebook icon and above is google sign in.
You probably started all over and tried linking your account , thinking it was gonna go to your account. But ended up linking to the new account. You cant link to your account during a new game. You have to link in the beginning after restarting the racing rivals app. And not after you seeing its a new game.