I was charged $64.99 for an in-app purchase that I never confirmed.

I was charged $64.99 for an in-app purchase. However, before making the purchase I was promted to update my payment information, which I did. After updating my payment information, I did not return to the app, but rather explored the internet for free alternatives, and finding one that suited my needs, abandoned my plans of purchasing the app. I never received any payment confirmation from Apple, and only upon checking my bank account balance this morning did I realize that I had been charged for the app. Seeing as I never confirmed that I wanted to purchase the app, never returned to it after updating my payment information, and never received a receipt after, how would I be able to get this charge removed?