Event Admin can also Block or Unblock the Time Slots of the Attendee.
Here are the steps:
- Go to the Appointments screen under MatchLeads
 - Select the Attendee based on a ticket category
 - Click on the three dots next to the attendee
 - Click on Calendar
 - Choose the date (If multi-day event)
 - Click on the Block/Unblock on the time slot and Save it.
 
Here are the images:
