The device will immediately factory reset and reboot. This takes 2–5 minutes. After reboot, re-enable USB debugging. In fastboot again, run:
fastboot devices You should see your serial number. Use the 16-digit code you obtained: How to Unlock Bootloader in HONOR 6 Plus phone
fastboot oem unlock 1234567890123456 (Replace with your actual code) The device will immediately factory reset and reboot
The phone will display a warning. Use to confirm. re-enable USB debugging. In fastboot again