Unable to update your fire tv stick endless loop

I've done everything the troubleshoot asked.

i unplugged it for more than 10 mins, and I restarted my WiFi box. 

Now it's stuck with that screen that it can't update my fire tv.

Answer:

Please factory reset your Fire TV device using the remote with these steps:

1. If needed, safely eject expandable storage.
2. Press and hold Back and right side of the navigation circle together for 10 seconds.
3. On the TV screen, choose to continue or cancel the factory reset. If you don't choose, the device resets automatically after several more seconds.

• Important: All account information and downloaded content is deleted during a factory reset.