How do I unlock the authentication settings in the user account section. I don't remember setting any password for it

[egrath]

Follow the instruction here:

Linux password lost

Press Shift during boot to enter the Boot menu Press e to edit the entry Append init=/bin/sh to the line starting with “linux” Boot with Ctrl-X Enter mount -a Enter mount -o rw,remount / Enter passwd USERNAME (USERNAME is your username) Enter the new Password Enter sync — wait a few seconds — Power cycle your machine

This will guide you on how to reset the passwords on your system.