Hi there. Don't worry! Let's take a look and see what happened.
A) I've already paid and received a notice that the card was processed, as well as a receipt from Apple, however I never received the item I purchased:

Please go to the Settings page on the Fortune City main menu. Then tap Restore Purchases. Look to see whether you have now received the item you purchased. If you still have not, please go to the Settings page on the Fortune City main menu and tap FAQ & Player Support to contact us. Be sure to attach your Apple receipt with your message to allow us to better assist you!

B) I've already paid and received a notice that the card was processed, however I haven't received a receipt from Apple or the item I purchased:

Please go to your phone's settings and tap your name, then tap iTunes & App store > Apple ID > View Apple ID > tap Purchase History. Look to see whether or not the purchase in question is on the list. If it is not there, or it is there but you have still not received a receipt and the purchased item after more than 24 hour since the purchase date, please use this page to contact Apple Customer Service.

What if you are an Android user? Please then see this tutorial.