They are able to charge your new card because your bank participates in the Automatic Billing Updater service provided by the PNO(Mastercard, VISA, etc.) The bank must actually block those future charges instead of just issuing you a new card number. The bank is well aware of the service they use, but many times first tier support just issues you a new card number where those charges will continue. More information about that service is available here and your specific bank may have additional details on how you can prevent the ABU service from being used to notify merchants of the change.
https://lastbastion.com/2025/03/19/how-i-stopped-unwanted-subscriptions-and-recurring-credit-card-charges-for-good/
I am not sure if Apple will be able to help with this process, but you can contact them here.
Contact Apple Support - Apple Support