You can export your contacts to your phone's SIM card, to prevent them from disappearing if your phone needs to be wiped.
First, open the Contacts app.
Select the hamburger ( Ξ ) icon, and tap 'Manage Contacts'.
You will be asked to select where you want to move your contacts from. Select 'Phone'. Then, select 'SIM' (this is most likely SIM 1, but could be SIM 2 depending on how your phone is configured).
After selecting the SIM, a box will appear asking you to confirm. Select 'Move'.
Your contacts have now been moved from your phone to your SIM.
Please note that a SIM can hold a maximum of 50 contacts, so you may need to be selective!
