Factory SIM unlock code of Microsoft Lumia 640 is available, which means permanent unlocking of Microsoft Lumia 640 is possible using a correct NCK code. We can unlock all Microsoft easily by IMEI. There is no need to change the firmware to open it if the phone prompts an unlocking code after changing the SIM card. Unlocking of Microsoft Lumia 640 by the code is the recommended method as you will not lose the phone's warranty. It is the fastest and secure method to unlock the phone by IMEI code. Unlocked phones can be used with all networks SIM card around the world.
To unlock your phone, we need only 15-digits IMEI. You can find the 15-digit correct IMEI by dialing *#06# on the phone.
The unlocking of the Microsoft Lumia 640 by code is a recommended method by the manufacturer. Since the unlock code comes from manufacturer database, it will unlock your phone 100%.