Amazon is currently having major server outages which are resulting in some Fire TVs and Fire TV Sticks reporting that they cannot access the internet. Fire TV devices periodically check to see if they can access the internet by pinging Amazon’s servers. If they can’t reach Amazon’s servers, the Fire TV assumes it doesn’t have a properly configured internet connection.
If this is happening to your device, the best thing to do is just wait it out. Modifying your network settings or factory resetting your device will not help. If your home screen is blank, you should still be able to launch apps from the Settings > Application menu.
Everything seems to be fixed and back up now.