Purchases

Hello!

See if this site helps: https://reportaproblem.apple.com. Then sign in with your Apple ID, on "I would like to..." select Request a refund. On "Tell us more..." choose a reason, tap next and select the purchase. Then next again and that's it. You should receive an email, and after 48 hours another one telling you if a refund is approved.

Have a great day!

Apple expedites the payment, the app needs to deliver it.

Go for a refund and try again or find a better app

This Apple support Billing Article should answer your question. 

Subscriptions and Billing - Official Apple Support 

Also https://reportaproblem.apple.com 

Also check Settings, your name, iCloud, Manage storage, change storage plan  

See this article about refund status 

Check the status of a refund for apps or content that you bought from Apple - Apple Support 

If Apple refused you then there is nothing else to do apart from legal action