Refund
I accidentally forgot to unsubscribe to a subscription and got billed for it, even though I emailed the app to report a payment error. within the 24hrs, they said to contact apple
iPhone 7 Plus, iOS 12.0.1
First, cancel the subscription: View, change, or cancel your subscriptions - Apple Support
Next, contact iTunes - Official Apple Support for assistance or fill out this form: https://www.apple.com/emea/support/itunes/contact.html
