Can you try
xrandr -d :0 -q
xrandr and see if that works?
If it doesn't... (Your profile lists that you are using both Lite and Core...) In Zorin OS Core (gnome) the configuration file should be
In Zorin OS Lite (XFCE), it is
If you are unsure, you can check with the command
sudo find . -type f -name "*displays*"
You can use the
mv command to rename them to a Back-up, allowing the system to set a Default Configuration.
For Zorin OS Lite:
mv ~/.config/xfce4/xfconf/xfce-perchannel-xml/displays.xml ~/.config/xfce4/xfconf/xfce-perchannel-xml/displays.xml.bak
For Zorin OS Core:
mv ~/.config/monitors.xml ~/.config/monitors.xml.bak
Once done, reboot and test.