DLC Cars & Credits Not Appearing

Bug Info: Just started playing the game this week, and completed the tutorial series. After completion, none of the purchased cars or credits have appeared on my account.
Platform: Windows PC
Edition: Premium
Account: solo account

Hi, could you please try this: go to forza support website, make a ticket, explain this problem to them, add a screenshot as a prove.
You can also try re-installing the game.