MyFitnessPal Charged Me $74 for an Unauthorized Premium Subscription

I downloaded the MyFitnessPal app to use for free, but even though I don't remember buying a Premium package, I found out I was listed as a Premium member in the app. I noticed that on May 11, my credit card was charged $74 for an annual Premium subscription, linked to the account I originally started on May 5.

I don't recall giving any authorization or clearly selecting a paid plan. The charge showed up on my card statement as "apple.com/bill," and when I checked my active subscriptions through my Apple ID, I saw that an annual Premium membership for MyFitnessPal had been activated. Since all my other subscriptions renew on different dates, I am completely certain this charge is from MyFitnessPal.

I went ahead and canceled the subscription through my Apple account, but I haven't been able to reach MyFitnessPal or their customer service to directly initiate a refund. I am requesting the permanent cancellation of this Premium membership, which I didn't want or knowingly approve, and a full refund of the $74 charged to my credit card.