macOS Ventura Shortcuts forgets keyboard shortcuts - solution?

This may have been answered elsewhere, but searching for help with Shortcuts is problematic.

My problem is that Shortcuts on Ventura keeps forgetting the assigned keyboard shortcuts.

Example. I have a shortcut that creates a string and adds it to the clipboard so that I can paste it into my app of choice. I trigger this using Cmd-Opt-Shift-N. I run this shortcut once a week.

Problem: when I hit Cmd-Opt-Shift-N, nothing happens.

What I expected to happen: the shortcut would run and a new text string would appear on my clipboard.

If I go back to Shortcuts and re-add the keyboard shortcut, it works. But next time I try to use the keyboard shortcut, Shortcuts has forgotten it.

This is clearly not the intended behaviour.

Is anyone else seeing this? Is there a solution? Is there even a way to search for keyboard shortcut problems with Shortcuts?

All help gratefully received...