You have wp super cache. Clear it’s cache content to allow updated content to load on your front page. You need to do this every time after you make any update in your WordPress admin.
After you have cleared cache content, you can check your permalink at Settings -> Permalinks
Use only one of the WordPress available setting, do not attempt to write your own custom permalink.
Go to Appearance -> Menus -> Manage Locations and check if your menu is properly assigned.
Clear cache content again, after doing above steps.