Thanks Talton, that’s helpful! Also, here is what disqus customer service suggested: “It looks like the issue is that the disqus_identifier variable is being set as blank in the source code. We suggest either filling in this value with a unique identifier for each thread, or removing the variable completely.”
Solution: I commented out the disqus_identifier variable in the disqus-comment-system/disqus.php file and this seems to be working. To do this, select Edit under the plugin, select the plugin file, and comment out this line: var disqus_identifier = ‘<?php echo dsq_identifier_for_post($post); ?>’;