Question: I accidentally deleted admin user name
I accidentally deleted admin user name and saved it. Now I unable to change system settings. Even though the user name shows as "admin" in Finder/Home folder, when I enter "admin" as User Name it says it is incorrect.
I found some help on how to change password by logging-in in the recovery mode using your Apple ID. But I cannot change User Name by doing it, just the password. Thank you.
MacBook Air, macOS High Sierra (10.13.3)