If some items are not showing on your Navigation Bar/Site Menu, the most likely cause is that you've set your link color or visited link color to the same color as the page background, so the links appear to be invisible (like black on black).
This can be corrected by changing the color in the Design | Color Palette section of your FASO account Control Panel. Ask us for help if you need it.
Otherwise, perhaps you've created a page but not placed it on your Navigation Bar. In that case, see our FAQ on how to edit that.