Small clinics feel every clash. One double booking can push the whole afternoon.
Set each doctor's available hours first. Booking should only offer times that exist.
Give every visit a status. A cancelled hour should return to the book immediately, not stay blocked because someone forgot to erase it.
When a patient asks to move, reschedule in the same record so reminders and the doctor's list stay aligned.
Clinivaan treats appointment management as part of the clinic day: schedule, status and the patient attached to the slot.