Thanks for visiting the Apple Support Communities and asking about the alert to verify your payment method. This can happen for a variety of reasons, but most importantly is used to protect you. I recommend verifying the payment method that is currently connected with your Apple ID. This article will help you: Change or remove your Apple ID payment information
That article also has the option to remove your payment method. This article has the different types of payment methods you can use: Payment methods that you can use with your Apple ID
This article has troubleshooting to assist you if you can't remove your payment method: If you can‘t choose None when you edit your Apple ID payment information
Thanks and have a wonderful day.