I’ve checked your website previously and it seems on the OneSignal Notification just works fine on the frontend (https://www.dropbox.com/s/p0dok16re60wkxn/Screenshot%202018-04-03%2008.35.58.png?dl=0). May i know which custom post type that you mean on this thing? Because we don’t have custom post type on JNews. Also, please try to disable JNews – Push Notification plugin if you want to use the original feature from OneSignal plugin. Looking forward to hearing from you.