Error when I try to create a new post

A recent issue has started on my blog. Whenever I try to create a new post, I get the error “Updating failed. Error message: Sorry, you are not allowed to edit the _edd_button_behavior custom field.”

I use the Divi builder for all my posts, so don’t know why this is happening, was never a problem before. I have the option to “leave page” which I do, then I write the post, but then when I schedule or make updates to categories, and try to schedule, I get other error messages. I have a post scheduled for tomorrow, will see if it goes up, but unclear why I am suddenly getting these error messages. I am the admin of the site.

The page I need help with: [log in to see the link]