Hi Shannon -
You may want to double check with Cvent Support to see if there is anything else you can do to delete the sessions, but based on this article, it does appear that the optional sessions can no longer be deleted if anyone has registered for them:
https://support.cvent.com/s/communityarticle/Can-I-delete-an-optional-session?is_article=true&lang=en_US&searchFor=delete%20cancelled%20session
If you can't delete them but want to push them to the bottom of the session list, you may want to mark them with a "Do not Use" in the name of the session (to help avoid confusion with the legitimate sessions) and you may want to change the session date and time to be after your last session, that way they appear at the bottom of the list (and it won't matter because the registrants can't see it but it will looker cleaner on the planner side).
Hope this helps!
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Becky Yousif
Senior Administrator - Event Technology
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