Hi!
– Did you add the shortcode directly to the post content manually or into the theme?
– Was it working before?
– Does it display anything if you put it elsewhere?
I can’t see any HTML code, which either means that there were no related posts found or the shortcode was placed incorrectly, I’m not sure.
Can you also provide temporary FTP and admin access so I can debug through the issue? You can edit your first post in this thread to add details or you can upload a .txt file.