reservations

Hello.
1) Firstly please note, this forum is only for support of Booking Calendar Free version.
Please contact support of paid versions here https://wpbookingcalendar.com/support/ or here https://wpbookingcalendar.com/contact/
2) If you need to make the specific number of bookings per days, then you need to check the Booking Calendar Business Large version, where is possible to make several reservations per specific FULL date(s) by visitors (not time slots). Please read more about it here https://wpbookingcalendar.com/overview/#capacity

You can test it in the live demo here https://bl.wpbookingcalendar.com/
Watch video about this feature here https://wpbookingcalendar.com/help/availability-capacity-video-overview/

At this version possible to set capacity of the booking resource, so date(s) in calendar will be available until number of reservations is less then capacity of the booking resource. But its possible to make booking only for FULL date, not a time slots (time slots in this version only saved as data into database, but do not apply to availability logic).
Highly recommend, to check this article about configuration of capacity and availability for booking resources: https://wpbookingcalendar.com/faq/capacity-concept/

Kind Regards.