How do I stop Apple.com/bill from charging my credit card

Nanajoyce wrote:

I did not make that purchase.

Who did? That is what needs to be determined and what actions should be taken.

For an in-app purchase managed by Apple, it requires a person to double click the side button, followed by verification with TouchID/FaceID or Passcode. That is not something that can be done by accident and if not done by you, then your phone has been compromised and you need to immediately change your Passcode, Password, and any financial accounts you have in your Wallet. This cannot be done remotely, so it would mean someone had physical access to your device and knew your Passcode. If you give someone else your Passcode, you have authorized them to make purchases.

With that information, what have you gathered when you review your Purchase History to identify what the charge is for:

View your purchase history for the App Store and other Apple media services - Apple Support

If you do not see the charge in your Purchase History, then it is not being managed by Apple and we would need to know the exact description of the charge you see. Any charge from a subscription/free trial made on a website will directly charge your payment method and it is not managed by Apple. To cancel those or request a refund, you would need to contact that website where the charge initiated.