OS : Debian Jessie 8.5.0
During setup, I defined a password for root and a primary user account.
Now, Gnome has only a standard account with restricted access.
I can't unlock settings, install an application, launch terminal, connect to a new wifi, etc.
I am also not able to manage user accounts since window is locked.
It's asking for an administrator password, root's and any
sus don't work.
Is there a way to change my primary account type in a terminal logged in as root ? Else, how to create an administrator account in my case ?