1. Download from support archive with custom recovery.
1.1.If drivers installed skip step 2.
2. Power on phone complete and install drivers, must be mounted volume with phone drivers, so install from this volume.
If custom recovery already flashed go to step 9.
3. Put phone in FastBoot mode holding Vol- and power On(5-10sec)
4. Put usb cable and wait until install drivers(check in device manager if all ok).
5. Open nckbox.exe, select Fastboot_utils tab.
6. Tick flash phone in recovery utils.
7. Click on load and send and select recovery image.
8. Wait until finish, remove cable, remove battery(for 5...6 sec, if not phone will auto power on).
9. put battery, keep Vol+ and power on until phone power in recovery mode.
10. Go to Huawei android tab, select correct model and press check.
11. If all ok press unlock.

Unlock need make from recovery mode.