We would like to perform some action on the website once the Pega chat is ended. We tried with following script with 'chatEnded' event . This doesn't seem to be working. Any idea what might be wrong here?

fireflyChatAPI.ready(function(){
fireflyChatAPI.chatHub.on({scope: 'chatHub', type: 'chatEnded'}, function() {
alert("Chat Ended");
});
})