Questions about a chargeback on a gambling website

So over Thanksgiving I had a bunch of family and friends over And my iPad has access to a gambling website that I use quite often and I have a bunch of transactions from before this but I have woken up early that morning and seen the total of 14 different charges totaling $5200 i’m not sure what I can do. Or if I’m able to do a chargeback, but I did not make these charges and had already reached out to the merchant and they said they couldn’t do anything because because the payments got authenticated via biometrics on Apple Pay and I’m not totally sure who could’ve done it I don’t know if it’ll be worth to try to get a charge back or if it looks like I’d be committing fraud so I don’t know if I should eat the charges or try to dispute them please any advice helps. Thank you.