"homer" and "root" are the same account. You can have multiple usernames for a single account. See also https://unix.stackexchange.com/questions/49993/another-account-with-same-uid-as-root-gets-prompted-to-set-new-password-for-root
You'll want vipw
and vipw -s
to fix this. Editing directly with vim
or sed
is a bad idea.
Consider https://serverfault.com/ or https://unix.stackexchange.com/ for future questions of this type.