How do I report a fraudulent charge on my Apple Pay account?

Hello,

If this occurred using Apple Pay in Messages see this article. How to avoid scams when using Apple Pay to send and receive money - Apple Support

"To report a scam or open a dispute for a transaction, contact us."

If this was a merchant transaction you should contact your bank. See your Apple Pay transaction history - Apple Support

"Dispute a credit or debit card charge made using Apple Pay

If you need to dispute a charge made using Apple Pay, contact your bank or card issuer."

I hope this helps.