New FB comments not shown under Recent Comments widget

Hello! I am trying this very promising plugin. I did have some WordPress proper comments, and some Facebook Comments Plugin comments prior to activation of this plugin. So far I noticed the following:

The pre-existing WordPress comments are no longer shown in the single-post view, even though they still are shown in the admin interface. Is it by design?

The pre-existing Facebook Comments Plugin comments are shown, however the comment count still shows the count of no-longer-shown pre-existing WordPress comments. Is it by design?

I clicked the “Sync Comments” button, it did show a success message (Yayy!!! Comments are successfully synced), but the comments counts stayed the same (still shows the count of no-longer-shown pre-existing WordPress comments). The pre-existing Facebook Comments Plugin comments are not shown under Recent Comments widget, and are not shown in the admin interface.

I entered a few new FB comments on a post that had WordPress comments. Now, the comment count updated to show the # of FB comments; however the new FB comments are not shown under Recent Comments widget or in the admin interface.

Any thoughts? I can send you the blog URL in a private message (I don’t want to publicly advertise this blog).

https://wordpress.org/plugins/facebook-comments-sync/