Did you make any updates? Could be version issues with your hosts. You could restore a backup of working site. 101 usually works
I'm a having a pretty weird issue going on with a Wordpress site. The URL is www.johnmichaelmarketing.com
The content from some pages is progressively disappearing and the site members can't even log into their accounts. There was a YouTube video in the home page and now it's not there.
You can see the pages content in the editor section but once it goes live it's like a ghost page. It all was working fine and all of the sudden it all started to fall apart. I haven't messed up with .php files or anything because it's not a theme I created and plus, it was working fine; I have no reason to do it.