Cannot access administrator account/sudo with same password as user account

I’m a relatively new linux user and I just installed Manjaro (dual booting with windows 10). On installation I do remember checking "Same password for administrator account" when asked. But every time I try to do an administrative action and type in my normal account password, or use sudo, it doesn’t work for some reason even though its supposed to be the same password as my user account. I have tried multiple times. What do I do to access admin.

(the reason I’m trying to use administrator privileges is to turn on the "Set time and date automatically" setting / timedatectl set-ntp true, both of these fail because the password I enter is apparently incorrect)

Make sure your user is member of the following groups lp, network, power, wheel.