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 starting from the bottom of the screen.
Press the profile icon.
Press Contacts app settings.
Press the name of the SIM.
Press the drop down list next to "Save to".
Press the fields next to the required contacts.
If you want to keep the imported contacts on your SIM, press Keep.
If you want to delete the imported contacts from your SIM, press Remove.
Slide your finger upwards starting from the bottom of the screen to return to the home screen.