My name is***** am sorry to hear that you are having this issue.
I will be glad to assist you with this.
This may be caused by a glitch in the firmware and can be resolved by a forced reboot, then your kindle will work normally again. Slide or press and hold the power switch for 40 seconds, then release. let me know if it downloads after the reboot please.
okay, if it fails we will try another option.
okay, try this please.
On your computer, go to Amazon.com
Log into your Amazon account.
Go to the "Manage Your Kindle" page.
Click the "Edit" link next to your credit card listed under the "Your Default 1-Click Payment Method" section.
Select a different credit card (if you have multiple cards on file with Amazon). You can also enter new credit card information under the "Pay with a new card" section.
Click the "Continue" button. The Billing Address page opens.
Select a billing address from the addresses you have on file with Amazon. You can enter a new address under the "Or enter a new billing address" section. Click the "Continue" button after you enter a new address. The Manage Your Kindle page reopens.
Then reboot the kindle again and try the download please.
Okay,Visit the “Manage Your Content and Devices” page ( http://amazon.com/mycd ) and locate the book in “Your Content” tab. Use the Actions […] button, choose “Deliver,” and select where to send the book from the drop-down list.If you’re not finding the book in Your Kindle Library, review “Digital Orders” to verify that the order completed. Start here: http://amazon.com/yourorders
Let me know if this does not work and we can try another solution.
Please reply and let me know if you need any other assistance,
Also, please take a moment to rate my service by choosing one of the stars at the top then click submit.