Hello,
Thanks for reaching out! Page Rules based on internally bound WordPress ID numbers (such as Category) may sometimes not work correctly. This happens when the editor received the value from the admin, but the frontend did not sync with the new info automatically. There's a button for syncing when this happens though... you will want to go into your Plugin Settings page in the WP admin and click on the “Sync With Dashboard” button:

After clicking on this button, then clear your website cache. This should result in the proper info being in the frontend, and the Page Rules working as expected.
Hope that helps!