Speakers details not displaying

I am using im-event-event-conference-wordpress-theme, i have created different speakers and i tried to click the speaker name it shows 404 page, the theme itself(no other external plugins used for this functionality) we can creates the speakers and groups inside the speaker tab section, any one has any idea about this? why it is not appearing? The url is coming like this https://domainname.com/speaker/speakername/, when i click the more details of the speaker it shows 404 error.