Hi there and welcome
What you need to do is add the card via your computer onto your account so it is updated on the Kindle
To do this
Visit the page for your account - https://www.amazon.com/manageyourkindle
- Log into using your Amazon account (the same Amazon account you have registered on your Kindle)
On the right side select "Settings"
Under 'Kindle Payment Settings' (first option)
Click 'Edit Payment Method'
Change your credit card details.
Restart your Kindle and it will update
It will then be updated
Let me know the results please