Comments Not Working

I’m running 3.8.1, and since 3.8, no new comments show up for anyone on my site. Not for me when I’m logged in, not for outside visitors.

They don’t work in any browser; they don’t work on Mac or PC. When I get a comment notification, this is what I get:

A new comment on the post “While You’re Away” is waiting for your approval
https://www.saundramitchell.com/blog/while-youre-away/

Author : (IP: , )
E-mail :
URL :
Whois : https://whois.arin.net/rest/ip/
Comment:

Approve it: https://www.saundramitchell.com/blog/wp-admin/comment.php?action=approve&c=0
Trash it: https://www.saundramitchell.com/blog/wp-admin/comment.php?action=trash&c=0
Spam it: https://www.saundramitchell.com/blog/wp-admin/comment.php?action=spam&c=0
Currently 0 comments are waiting for approval. Please visit the moderation panel:
https://www.saundramitchell.com/blog/wp-admin/edit-comments.php?comment_status=mo derated

When I look at the dashboard, there is no comment anywhere. Comments are enabled, and they worked fine until about mid January when they abruptly stopped.

My host company has been trying to figure out the issue for about a week now with no luck. They suggested that I come here for help.

One of the still-comment enabled posts is here:

https://www.saundramitchell.com/blog/?p=105#comment-

I have already tried:

Accessing the site in Safari, IE, Chrome, Firefox with and without extensions enabled.
Disabling all plugins
Deleting all comment plugins
Resetting plugin folder via FTP
Reverting to default theme
Reverting to default permalink style
Replacing the comment.php file with a fresh one
Downloading a new copy of WordPress and reinstalling
Creating another installation of wordpress on my server (Comments work on the test installation.)