Why was I charged for Audible when it was suppose to be a 30 day free trial 1 week into the free trial?

I started what was supposed to have been a 30 day free trial of Audible and Apple charged me! Apple took the money from my Apple Pay around 1 week after I started the free trial! First thing why did it take Apple so long to process the payment to begin with? And Apple had no right taking any money for a free trial! The money may go through Apple Pay but the Audible app belongs to Amazon and the free trial was through Audible! So why did Apple take money for something that was was supposed to been Free? I contacted Audible and they said Apple wasn’t suppose to be able to do that! I appealed it and Apple denied it! So Apple basically took my money and refuses to pay me back! I want to know what can I do fight this appeal and get my money back?