General comments stops working after one non-Facebook comment

I’ve installed Ultimate Facebook on What is working:

Sending a post from WordPress to a Facebook Fan page.

Showing replies on the WordPress page to the post sent to the Fan page.

Being able to reply on the WordPress site to comments made on the Fan Page.

All of the above works for a reply made to a post made on the WordPress site and posted to the Facebook wall of the person creating the reply.

What isn’t working:

1. A person who does not use Facebook attempts to reply to a comment created in WordPress. The person, when they attempt to post the reply receives the following message:

“ERROR: The solution of task you submitted was incorrect. Please read the instruction and try again.:

2. A person who does not use Facebook attempts to enter a comment in the WordPress site after an initial comment has been made. That person receives the same message listed above.

Basically, after the initial comment, no more comments can be entered by anyone, except in response to Facebook comments.

I need to be able to allow non-Facebook users to make comments in the WordPress site and reply to non-Facebook comments. What needs to be done to make this happen? I can send you screen shots of what is happening.