ⓘ This article is for Event Organizers
As the Event Owner and Event User you have the ability to change a registered attendee's selected sessions anytime before the session begins (those sessions that they selected at the time of completing their registration process).
Steps
From the Admin Home Page, click Sessions in the left-side navigator.
Enter into the session or add a new one
Click Add / Edit in Session Attendees
Search Registrants Assigned to This Session.
Once found, click the "x" to the right of their name, which removes then as a Registrant
Once done, click Save Registrants
Congratulations -- you have now removed this attendee from this Session.