Gee, perhaps an indication of how to set up your plugin would help. Maybe a "go here to set up." It always amazes me that developers spend so much time developing a plugin, but almost nothing on how to use it. Others having the same problem from what I see in the comments. Uninstalled and added a different plugin that does the same thing.
This plugin works perfectly on my site. I have tried many similar plugins without any luck. This one is easy to translate and work nicely with rtl sites. Check my site at KihaadhooLive. This is a Dhivehi language wordpress site which is an rtl site.