Can’t really tell what’s happening. Could be some caching going on. I still didn’t see the list of sheets until I held down shift and reloaded the page a couple of times.
If you have a caching plugin, make sure you disable it on any page like this which has dynamic content.
If that doesn’t work, maybe go to your permalinks page (admin settings for WordPress) and just hit save again to clear any weird permalink issues.
Otherwise, it’s hard for me to figure out what’s going on. If you’re using some kind of block editor, visual editor, in your theme or plugin, maybe try putting the shortcode in a different kind of block (like a pure HTML block).
At this point, I’m just guessing, without being able to see your admin setup and what else is going on.
If you installed some new plugins, maybe try deactivating those one at a time and rechecking the page, to see if you can find a possible conflict.