How to remove payment method

In order to remove a payment method, you will need to update your payment method first, so that you do have a payment method on file.

See this instructions on how to do that

1. Open the Settings app.
2. Tap your name.
3. Tap Payment & Shipping. You might be asked to sign in with your Apple ID.
4. Tap Add Payment Method, enter the new payment method, then tap Done.
5. Tap Edit.
6. Tap the red delete button next to the old payment method, then tap Delete.