You can import your contacts from your SIM to your phone. This way, you won't lose your contacts if you change your SIM.
Slide your finger upwards on the screen.
Slide your finger right starting from the left side of the screen.
Press the required SIM.
Press the drop down list next to "Save to".
Press the fields next to the required contacts.
If you want to keep existing contacts saved on your SIM, press Keep.
If you want to delete the existing contacts saved on your SIM, press Remove.
Press the Home key to return to the home screen.