HTML Code is erased when User updates page


I'm using Avada Fusion builder theme and if I (as super-admin) have put html code in the "text" part of the Fusion builder, it saves and is fine. But if any other user updates any other part of the page it wipes out some or all of the html. At the moment it's happening with a PayPal button but it's also happened with trying to embed google maps too.