refund for myfitnesspal subscription

Myfitnesspal and Apple are very unfriendly to non-English users. The advertisement indicated a 30-day trial period, so I confirmed on 3/14, only to later realize it was a confirmed payment subscription. I have already cancelled the subscription on the app on 3/22, but Myfitnesspal said they cannot refund to me because to Apple. I just wanted to try this app in a free version, please help to refund.