Slots can become unselectable for several reasons:
Slots are marked as unavailable
If the instructor has created blockings, the system will mark those times as unavailable, even if the lesson is active.
Product date restrictions:
Lessons have buyable From and buyable To dates. If today’s date falls outside this range, the lesson becomes disabled and cannot be selected.
Minimum product duration vs available time
If the instructor does not have enough consecutive available time to fit the lesson’s minimum duration, no slots will be available.
Example: If the shortest lesson is 60 minutes but the instructor only has 30-minute gaps, nothing will be sellable.
Resource availability issues
If the lesson requires external resources such as simulator bays, and those bays are not available at that time, the slot will be unselectable even if the instructor is free.