That is not a valid site, but you do need to do this on your computer, not the kindle.
First, go here:
there you can be sure your card/bank info is correct (right address, valid expiration date, etc)
From there, go here:
On this page, click on the SETTINGS tab at the top right,
then you can from there set a default card to be used for one click purchases on the kindle.
Under Kindle Payment Settings, click on the Edit Payment Method button, and you can set the card you want used for your kindle purchases.
After that, reboot the kindle by pressing/sliding and holding the power button for 20+ seconds, and it should operate normally from there.
If you have any other questions, just let me know. Otherwise, please do remember to rate my service prior to logging off, hopefully I have earned an “excellent”. I also invite you to contact me directly with any future support needs at http://bit.ly/1gHgwli
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