When getting a popup message to Authenticate as “administrator” in gnome it most likely means the user you are using does not have the correct groups associated to them.
Some of the messages you see were “Authentication required to refresh system repositories”
When rebooting or relogging in, it will now show your username to authenticate instead of “administrator”
Add the user to the
sudo usermod -a -G adm <username> sudo usermod -a -G sudo <username>
Not exactly related – but similar issue: