Plugin Widget Not Visible in Comments Sectiom

Hi All,
I installed the plugin into this blog yesterday, and it was working great. However, the plugin doesn’t appear at all anymore for users in Chrome or Firefox. It does, show up in IE, however. Any suggestions you can recommend? http://www.matmotmi.com/2013/08/09/119/

I tried deactivating the plugin and then reactivating it, but the plugin still does not appear.

http://ww.wp.xz.cn/plugins/fatpanda-facebook-comments/