Karen, here is what Amazon says "If you're having problems opening a book from your Device tab, try redownloading the book:
From the Device tab in your Books content library, press and hold the title of the book you want to delete.
Tap Remove from Device.
Tap the Cloud tab, then tap the item to start redownloading it again.
If you see an error message when downloading a book from the Cloud tab, try tapping on the title again to restart the download.
If you're still having problems, try restarting your Kindle Fire: press and hold the power button, tap the Shut Down button when it appears on the screen. After the device has completely turned off, press the power button to restart your Kindle Fire." From here Of course you also have to make sure the Kindle is set to Device and not the Cloud. It is possible that the book is on the device, and if it is not, make sure you download it to your Kindle. Give this a try and let us know.