Hi Pam,
I had something similar happen to an event last year. Below is what I did:
What I did was go to Agenda, search for your session and then click the number of attendees that are registered to that slot. It should then take you to the attendee list where you can find the attendee and put a check mark next to their name. Then go to Bulk Actions and select update session registrants. It will bring a pop-up window, in the Update Method select 'Unregister all from session', search for the session, click on it. It will give you one more screen to choose to confirm. Sometimes it gives the option to notify the attendee, I always uncheck that box.
For the limited visibility are you using Audience segments in your agenda or Advanced Rules?
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Rebecca Pebley
Advanced Systems Senior Manager
SHPEUnited States
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