There are 2 options available to display the timeslots on your ordering system:

Option 1: Display both available & unavailable time slots.

Setting: Show time which are not available = YES

This is the preferred option, as it allows your guests to see all timeslots so that they are aware that these are all available to order (subject to availability)

Option 2: Only display timeslots that have availability.

Setting: Show time which are not available = NO