This indicates a communication failure between the computer and the Amlogic storage controller.
While holding the button, connect the USB cable to the (usually the USB port closest to the HDMI port or SD card slot) of the TV box.
This method works for 90% of S905L2 boxes.
The progress bar will turn green and display the percentage.
Swap your USB cable to a different port on your PC. Ensure you are using a rear motherboard port if you are on a desktop computer. Avoid using external USB hubs. Error: Stuck at 2% or 4% ([0x32030097] ROM Erase Error)