Launch Car Pack Missing

I pre-ordered Forza 6 (digital version) and it said that I would receive a Mazda MX-5 Car Pack and a Forza Ten Year Anniversary Car Pack. I have already checked that they are downloaded on my Xbox and when I go into the marketplace I can see the little ‘purchased’ sign on the cars. However, I can’t buy them for free when I look for them in the ‘find a car’ section. All the cars still have their original prices. There is no ‘free cars’ section and I have already tried reinstalling. What do I do?

have you hard reset your console since installing…should be the first thing to try

Snowowl explains hot to do it properly here