Can't edit posts – "Editor not found"

When I go to write a new post, it allows me to type in my title in the title bar, but it won’t let me write the actual post in the text box. It says “Editor not found”. I also deactivated and activated my Plugins one by one like I saw on other posts, but it still isn’t working. I know nothing about code and only the basics of WordPress so step-by-step instructions would be a great help.

Here’s the link to our blog:
http://apotheblog.murrayavenuerx.com/

Thanks!