Facebook comments appear twice!

Have you added the shortcode to your template and not disable automatic addition?

How do I do that?

I assume by your reply you haven’t added it manually. Uncheck to show on posts and pages. Do both disappear?

Yes. Both disappeared.

I unchecked show on posts and pages. Then I added [fbcomments] to my post and both comments appear again.

What am I doing wrong?

Can you deactivate other plugins and see if it still happens. If it does, swap themes to a default WP theme to see if it still happens. Then please check back with me…