I am using post notifications shortcode and newsletter shortcode in the popup plugin. The post notifications seem to work perfectly where it submits and shows a success message. The enewsletter shortcode display ok but when filled out and button clicked to subscribe it does not do anything or give a success message. On the backend, it is not received either. How can I get the enewsletter shortcode to work just like the post notifications (i.e. subscribe by email plugin) in the Popup Pro?