I’m still paying for a phone that is lost/stolen.

Hello shakera177,

Thanks for visiting Apple Support Communities! We understand that you're wanting to remove your lost device from your monthly bill. If this is for monthly payments toward the AppleCare plan, these steps will help: Cancel or change the payment method for your AppleCare plan

If this is regarding the device itself, you'll want to reach out to the financial institution that is financing your device.

Thanks again, and take care.