Hi, have you seen this plugin? – https://wordpress.org/plugins/genesis-404-page/
That should help. There are also some Custom ways of doing it by adding in the Code/Template yourself. But give the plugin a try first and let me know if that works for your site.
Also, I’m not a Moderator, I’m just a Customer (like you) so I don’t have access to any options of making this thread Private. So you may need to notify a Moderator, or contact Appfinite through their contact forum in order to remove or make this thread private.