Did you customize the module in anyway? It obviously should not be showing both. If you didn't try to change the template for the module, I would recommend uninstalling the JFBCLogin module in the extensions manager and then re-installing it. You can find the JFBCLogin zip file in the /admin/packages directory of the main component installation zip file.
Let us know how that goes, or if you run into other issues.
JFB Login module duplicate messages?
