You too have rewards waiting for you. To redeem these you only need to go to your apps and search for Forza Hub. Once you have done this it will tell you exactly how much you are entitled to. Keep in mind it takes up to 4 hours for this to appear in your account though.
I believe the minimum amount you will receive is 300,000 but depending on just how much Forza you have played your rewards could be huge and previous Forza games also count. So if you haven’t already done this be sure to jump on it.