for some reason when i trigger my webhook in make to schedule an appointment through vapi, it doesnt get shceduled and sends a webhook repsonse that the time i choose isnt available even though it is... it also gives me code 200 from make with available slots

Ensure Make returns the expected JSON structure with the correct toolCallId and availableSlots, all systems use the same time zone, and responses are timely for Vapi to interpret correctly..