Looks like it’s resolved. In general things to check are:
1. Check that the page template has a wordpress comment box div defined in the HTML (this is where the comments will be placed). The HTML code looks like:
<div id=”commentform”>
<!– … –>
</div>
2. check that javascript is on, and there are no javascript errors on page. Also, very old browsers (like IE 6) are not supported by Facebook.
3. If mail is not going through, try using SMTP (for example with the WP Mail SMTP by Callum Macdonald (https://www.ads-software.com/extend/plugins/wp-mail-smtp/)
thanks,
Kevin