If you see ‘itunes.com/bill‘ or an unfamiliar charge on your bank, credit card, or debit statement - Does not mention purchases made under Family Sharing which might be charged to the organizer's card but will not appear under the organizer's purchase history.
https://support.apple.com/HT201382
Request a refund for an App Store or iTunes Store purchase - https://support.apple.com/HT204084
Click here to Report a Problem or ask for a refund --> http://reportaproblem.apple.com
- "Sign In for help with iTunes purchases made in the last 90 days" Subscriptions aren't managed through this link, see https://support.apple.com/HT202039
View, change, or cancel your subscriptions - https://support.apple.com/HT202039
If you have unsatisfactory results with Report A Problem or this is for a subscription then:
iTunes [Store] Support - Use this form for assistance with account and billing, code redemption, or purchase questions - https://www.apple.com/emea/support/itunes/contact.html
Worldwide iTunes support - https://support.apple.com/country-selector/itunes