Hmm... I might have actually asked about the wrong problem. Im logged in with the only user account on the machine and that's an administrator account. I actually do remember and can enter the password for this.

I don't actually recall setting a root password for the account which is probably why it's failing.

I encountered this when updating bazzite, after it's done its thing, it asks if you want to press R to reboot. When I do that it asks for the sudo password, which I guess I don't have? What should I have done/do now?