If your OneKey Pro displays a "Fatal Error" on the screen when powering on, you can follow this tutorial to troubleshoot the issue.

Enter the device's Update Mode

Press and hold the power button to turn on the device.
When the OneKey logo appears on the screen, swipe your finger from the top-right corner to the bottom-left corner of the screen in a straight diagonal line. Repeat this 1–3 times.
When the device displays the "update mode" screen, it means you have successfully entered Update Mode.

Firmware Upgrade

After entering Update Mode, you can upgrade the firmware using either of the following methods:

For a more complete upgrade process, please refer to: Firmware Upgrade Tutorial.

If the startup error persists after the upgrade, please take a photo of the error screen and contact official customer support for registration.