I dont know what Version you are using or what country but in Version 22.4.2 german layout it is the same. On german Keyboard its CTR+, to hide the guidelines. I found that there is a conflict with Hide Layers, that uses the same Keyboard shortcut. Go to Keyboard shortcuts and delete the shortcut at Hide layers and all works fine.
It still works for me. Have you inserted any ruling guides? You can only show/hide them if they exist. (Drag them from the ruler or insert them from the View menu first.)
Are you on Mac or Windows? Which version of Photoshop? It works for me on 22.2.0 release for Windows. Perhaps you have remaped that shortcut somehow? Check that you have that shortcut on the right side of menu item then try to reset preferences. Save all custom actions and presets which are not saved to avoid losing them.
I am always using Ctrl + H but that will hide all extras.