Open your terminal and navigate to the folder containing the token.

You can relock the bootloader much more easily if you ever need to sell the phone or claim a warranty.

Run the following command: fastboot flash cust-unlock unlock_token.bin If successful, you will see a "Finished" message.

Here is everything you need to know about why this happens and how to resolve it the right way. Why Am I Seeing This Error?

In Settings > System > Developer Options , toggle on OEM Unlocking and USB Debugging . Get your Unlock Code: Connect your phone to a PC with ADB installed. Open a terminal and type: adb reboot bootloader . Once in fastboot mode, type: fastboot oem get_unlock_code .