I created staff group for Staff and the Board of Directors, and added them to the menu on the site. It was working for a little while but now it’s not displaying. The main staff page still works but not the staff groups.
Often when there are not found errors in WordPress it is related to permalinks. Go to Settings in your WordPress dashboard and choose Permalinks. Scroll down to the bottom and click save. That will clear out the permalink cache and hopefully fix the trouble for you.
If it doesn’t, try switching to the default permalinks and see if that makes a difference. Let me know they are still appearing as not found for you.