Timeslot shows up while no places left

I have set my ‘Maximum booking count per time slot’ on 10 and made a reservation for 10 spots. When I try to make a new reservation the timeslot still shows up, but I can’t select any places.

When I go to the Appointments menu and manually create a new appointment I can’t select that certain timeslot, like it should be.

I would like that visitors can’t see the timeslot when it has 0 places left.