How to MFA Local Administrator accounts on Servers

Trying to MFA local user accounts, works for everything except… how to MFA the local ADMINISTRATOR account? I tried adding in \Administrator but keep getting the “this username you have entered is not enrolled in DUO Security.”

I Looked everywhere cant seem to find any good documentation on it.
Do I need to rename each local Administrator account o something unique in the enterprise?

Do you have a user in Duo named Administrator? We have MFA turned on for the Administrator account for our Domain Controllers, however I guess this may technically be a Domain User account and not a local account.

On your Domain controller, there is no local administrator account.