Reward cars don't fully work

I have a problem with cars that are unlockable for drift chains, scores, races, etc. However, I have already "unlocked" a lot of cars but they do not show up either in vMenu or under the *rewards command. I have unlocked 3 cars but these are the ones I unlocked a while ago and the ones I unlocked now don't show up. I looked at a few other posts but none matched this one (if I missed something, forgive me). If anyone has a solution for this, I'd be very grateful. Thanks in advance and have a nice day.