In Belarus, ZTE MF 637 Life Modem is very famous and can be unlocked through two processes. The first is through DC Unlocker cracked version, and the second is the firmware upgrade process.

Read: How to use DC-unlocker cracked version?
How to unlock Belarus ZTE MF 637 Life Modem free using DC Unlocker cracked version?
1. Download the DC Unlocker cracked version from the above article link.
2. Now, unzip the downloaded file and extract it to a folder.
3. Now disconnect from the internet and change the SIM card with another network provider to detect the ZTE MF 637 Life modem properly by DC-Unlocker software.
4. Now plug the modem into the PC and let it install all the required drivers.
5. When the dashboard/software of ZTE MF 637 opens up, close it.
6. Run DC Unlocker cracked version.
7. Go to the ZTE tab.
8. Now click on the search magnifying glass.
9. Now, after successfully connected your modem to DC-Unlocker, click on Unlock.
10. Now your modem is unlocked forever.
If you don’t want to use DC Unlocker cracked version, then download the firmware of ZTE MF637 firmware ERA DL_MF637_TMO_PL_0B05V1.00.00 from the Polish operator. Update the firmware of your Belarus ZTE MF 637 Life dongle, and it will unlock your modem forever.