Hey Maddy, thanks for getting in contact with us about your wallpaper changing when you restart your phone. We would recommend reaching out to our technical support team for assistance on this, they'll be able to troubleshoot the issue for you and walk you through next steps. You can reach them on 0800 726 786 (24/7) or live chat on http://livechat.support.samsung.com/Customer_new/NZ. Cheers, The Samsung NZ Team.
