As a dual OS user, I run both Windows and Ubuntu. But mostly Ubuntu is my preferred OS. For the last 1 month or so I did not use Ubuntu. So when I came back to Ubuntu, I face some critical issue on my system. And one of them is system settings disappear.
So we reinstall the system settings and that works. Here is how we did it.
Open up the ubuntu terminal by pressing CTRL+ALT+T or search from Ubuntu search panel.
and run the following commands
sudo apt update
sudo apt install --reinstall gnome-control-center
Press ‘Y’ if asking for permission.
Once the reinstallation has completed you can get the system settings from the search panel or run the following command from a terminal to run system settings.