System Preferences shortcut not working

In System Preferences > Keyboard > Shortcuts > App Shortcuts - All Applications selected. Click the + symbol, type in "System Preferences…" in the "Menu Title:" field, then "command shift ," in the "Keyboard Shortcut:" field. Make sure to use an ellipsis (option ;) after "System Preferences" and not three periods.

Have read this thread two [now three] times and cannot understand

the need with any Mac (with both dock & apple menu bar in place)

to also have a cumbersome 'keyboard shortcut' to engage Sys Prefs.

Please explain if you have attempted to reverse this shortcut, what

you have tried; and if you have or not attempted alternative startup

shortcuts to such as Safe mode; or if macOS Recovery was tried.

You can start in recovery and use tools there to repair/install an OS.

Or reverse what you've done, and try again to make it work.

More than one (some similar) shortcut methods appear in search result:

https://duckduckgo.com/?q=mac+system+preference+shortcut&t=ffsb&ia=web

Good luck & happy trails!🌞

I agree completely with K Shaffer: I don't understand what you are trying to achieve and why.

Anyway if it is about shortcuts:

look in SystemPreferences->Keyboard->Shortcuts and surprise yourself.

Glad to help.