Hi Manuela,
The Waiting list feature works like this, when the timeslot is booked by someone, it will be occupied, at this time, the link "Add to waiting list" will be shown, and different customers can add their Name, Email to keep their information in OS Services Booking, by some reasons, the timeslot is available again, OS Services Booking will send the notification to subscribed customers to inform them that the timeslot is available for booking now.
To make this feature available, you need to setup some configure options below:
1. Enable Configure option: "Turn on Waiting list"
2. Enable Configure option: "Show Occupied Time Slots"
3. In configure option: "Select Timeslot Theme", please select option: Radion theme".
Thanks
Dam
