Welcome and thanks question.
I'm Todd and I will be the expert working with you today to help resolve your problem.First of all sorry late response. Your question was locked by another Expert.
Don't worry, all your books are stored (and safe) on Amazon cloud. So, none of your purchased books will be lost.
Sometimes your Kindle can be unresponsive and keep you from using the device properly (the most important reason issue can be glitch in the software). If there is no hardware issue on the device, some of the solutions below should resolve this issue.
Please follow the steps below to reset your device:1. Press and hold (or slide and hold) the power button 35 seconds.
2. After 35 seconds, release the power button.
3. Wait 2 minute, then turn on your Kindle.
4. Test your Kindle (try to charge it).
If that doesn't help, please try the next troubleshooting step.
1. Disconnect the power cable from the wireless router (turn the router off)
2. On your Kindle -
Press and hold (or slide and hold) the power button 35 seconds.
3. Allow up to 3 minutes Kindle to reboot.
4. When Kindle reboot, turn on your router and wait 2 minutes.
5. After 2 minutes, try to connect your Kindle to wifi.
If previous solutions doesn't help the next step will be:
1. Go to the link below (use your Amazon username and password ***** log in) -
click hereAfter log in you will be prompted with the "Manage Your Content & Devices" page (check the picture below)

2. Find the book you want to transfer to Kindle on the list and select it.

3. On the left side, click on "Actions" and select "Deliver".
4. Find you new Kindle on the list and select it. Confirm using yellow "Deliver" button.
5. Sync your Kindle (from Home, select "Sync" or "Sync & Check ).
Please try all solutions (step by step) and let me know if that works. I'll be waiting reply.
If none of those solutions works or you need more information please do not rate my answer negative BAD service or POOR service. Reply to me using "Reply to Expert" button and I'll provide you with the next step.Kind Regards,
Todd