Hello, You need to change your "One Click Payment" options on your Amazon account, and you need to do it from a PC or laptop- you cannot do this directly from your Kindle.
To view or edit your 1-Click payment method:
If you need further assistance let me know. Please do not forget to click the 5 STAR RATING, at the top of the page for my efforts. It is my livelihood and you can follow up at any time if needed.
Please let me know when you are able to see my reply.