Changing from Administrator to Device Owner

In shadow I hit Windows + R and typed “netplwiz” and hit enter. I hit properties, went to the Group Membership tab, and changed my account from “Administrators” to “Device Owners”. Now my account is classified as a guest, and there is no other accounts on the device. When I try to change it back to Administrator, it asked for admin permissions and my only option is “No”. I’m running shadow on a Windows machine using the Official version. I believe my only option is a factory reset, and if so I would like a way to back up all of my files.