Find what you've bought from the iTunes Store and App Store on your computer. Here is the instruction https://support.apple.com/HT204088
If you can't view your purchase history on your computer, you can see your purchases from the past 90 days at reportaproblem.apple.com.
Sign in with your Apple ID.
Find iTunes receipts.
Make a screenshot and send us. Please describe your problem for our team so that we know what we should look into.