If you change SIM or mobile phone, you can copy your contacts between your mobile phone and SIM, as it saves you from keying in all the information again.
Find "import from SIM"
Import contacts from SIM to mobile phone
Return to the home screen
Tap the dots in the bottom right corner of the display.
Tap import from SIM.
Tap the home icon to return to the home screen.
*Please refer to the Microsoft website for more information or further support.*