To reset an Amazon Fire TV Stick to its factory default settings, you can follow these steps:

Note: Resetting your Fire TV Stick will erase all your settings and data. This includes installed apps, preferences, and login information. Make sure to back up any important data before proceeding.

1. Turn on your TV and make sure it’s set to the input channel to which your Fire TV Stick is connected.
2. On the Fire TV Stick remote, press and hold the “Back” button and the “Right” directional button simultaneously for about 10 seconds.
3. A pop-up message will appear on your TV screen, asking if you want to reset your Fire TV Stick. Use the remote’s directional buttons to highlight “Reset” and press the “Select” button.
4. Another confirmation message will appear. Use the directional buttons to highlight “Reset” again and press the “Select” button.
5. The Fire TV Stick will now begin the reset process, which may take a few minutes. The device will reboot and return to its factory default settings.

After the reset, you’ll need to set up your Fire TV Stick again as if it were a new device. This includes connecting to your Wi-Fi network, signing in with your Amazon account, and re-downloading any previously installed apps.

Resetting your Fire TV Stick can help resolve various issues or prepare it for a fresh start. However, be aware that all personal data and settings will be removed, so consider resetting it as a last resort after trying other troubleshooting steps.