First, get the correct WiFi password ***** your laptop. Follow the steps below to get the WiFi password ***** your laptop.
Click on the network/wireless icon at the bottom right of the screen (left to the clock)
From the list of networks, right-click on your wireless network name and click on Properties.
Then click on the Security tab.
Then click the box at Show characters.
This will show the password ***** the text box.
Another way is, press Windows and R keys at same time and this will bring Run window. Type ncpa.cpl and press enter. You will see the WiFi network adapter (with a Wireless icon). Right click on it and select Status. From the resulting window, click Wireless Properties button and click "Show Password" to see the password (under Security tab).
Once you get the password, do the steps below;
On your Kindle go to Settings > WiFi. You will see the list of WiFi networks there. Tap and hold down your WiFi network and tap Forget. Or tap the WiFi network and tap Forget. This step is important. Then reset your Kindle. To do that press and hold down (or slide) the Power button of Kindle for full 40 seconds and this will reset the Kindle.
Now turn off your router and unplug it for 2 minutes (this will soft reset it). After that turn it back on. Then on Kindle, go to Settings > WiFi. Select the WiFi network and enter the WiFi password ***** got from your laptop. Connect
Please let me know if that didn't work, so we can continue troubleshooting.