If you don't want to allow non-registered participants, go to Settings > Bookings and rules and uncheck "Allow unregistered clients to book." Related ArticlesHow to Create a Long-Term Course with Multiple SessionsLogged-in vs. guest client when booking — what's differentClients: duplicate client profiles — how to resolve them without losing dataWorkshops and courses without online booking (information only)How to send a door code only to clients with a booking