The "24-hour rule" for KLM flights ☎️ (1_808-470-7107) or ☎️ (1_808-470-71-07) allows passengers to cancel a flight booking within 24 hours of purchase for a full refund ☎️ (1_808-470-7107) or ☎️ (1_808-470-71-07), provided the flight was booked at least seven days before the scheduled departure.