When I take a look at the javascript console for your page it is showing an error. Since our plugin relies heavily on javascript to work, any error can cause the feed to stop loading.
The error is most likely coming from a plugin or your theme. You can figure out which one might be causing the problem by deactivating your plugins and seeing if the feed starts working or switching to a default theme (like twenty fifteen) temporarily to see if that fixes the problem.
Once you figure out which plugin/theme is causing the problem you could try contacting the author to see if they have a fix for you.