Launch DC-Unlocker client
Open Server tab, enter your username and password that you received after credits purchase. Click "Check login". (you can buy credits here www.dc-unlocker.com/buy).
If DC-Unlocker/Vygis/Rocker/Infinity dongle is connected, only click " Check login ".
Detect device by selecting ZTE modems from manufacturers drop down menu list, leave Select model as auto detect (recommended) then click magnifying glass button
Wait till program detects device
NOTE: if device is not detectable, please check this guide here to bring modem to ports manually
Open Unlocking tab, click “Unlock” button
Wait for device to be unlocked
After you see that modem was successfully unlocked, restart it by disconnecting and connecting back. Now you can use it with any SIM card.