How to get a refund from an iPhone App that took money without permission?

Nibble took a year’s subscrition from me although I immediately cancelled the subscription after just looking around for 10 minutes. Thats a lot of money - In South Africa that is a month’s salary to some people. I want my money back. They are skelms.

Nibble App did the same to me. I've canceled my subscription but they charged me for another month ..

If you have received an invoice from Apple, tap on Report a problem on the invoice.

Then you can choose an option:

OR see -> Find the URL for an app in the App Store to report a concern

Find the URL for an app in the App Store to report a concern - Apple Support

I believed I was on a trial basis with Nibble since I am a professor of art history, and was interested in how art history was presented in this app. I wanted to catch a glimpse and then cancel, unless of course unless it was full of new information that I could research and present to my students. Although it was informative, I found very little of it useful. When I attempted to cancel my "trial" I was informed that indeed I could cancel, but they were keeping my $29.99. I persisted and emailed several times, stating that I would not be giving a very good review if my money were not returned. Needless to say I am $29.99 poorer yet wiser for the next time I am scammed.