If your phone runs Android 8 or later with latest security patch - then this service won't work! For devices with Android 8 and later check this guide HERE
IMPORTANT: Connect phone to PC. Then, enable "manufacturer mode" on your phone. This is done by entering in dial pad code *#*#2846579#*#* (On tablets without dial pad use inbuilt calculator in landscape mode to dial ()()2846579()()= marked in red), select "Project Menu", "Background settings", "USB ports settings", "Manufacture mode".
Install drivers for your phone by downloading and installing HiSuite software. After driver installation your phone in device manager should look like in the image below or appear under "Ports" section at least.
Launch DC-unlocker software
Detect device by selecting Huawei phones from manufacturers drop down menu list, "Select model" leave on Auto detect (recommended), then read the info on software for how to correctly prepare phone for detection. After phone is prepared, connected to PC and it's drivers installed, click magnifying glass button
Wait till program detects it
Open Server tab, enter your username and password that you received after credits purchase. Click "Check login" button (You can buy credits here www.dc-unlocker.com/buy). If DC-Unlocker/Vygis/Rocker/Infinity dongle is connected, only click " Check login "
Open Unlocking tab, click “READ BOOTLOADER CODE” button
Wait for code to be provided
You can restore phone now to it's original mode, otherwise it might not function properly
WARNING: Credits lost for reading bootloader code on not support models are not returned or refundable!
Officially supported models for bootloader unlock code reading here