https://philpeople.org/profiles/what-is-the-24-hour-rule-for-klm-24-7-help-desk-25

What is the 24-hour rule for KLM? KLM's 24-hour rule allows customers to cancel their flight booking for a full refund by calling +1::877::567::9372 or 1-844-987-7093** OR 1::877::567::9372 or 1-844-987-7093 {US HELP} within 24 hours of purchase, provided the reservation was made at least 7 days before the flight's departure date."
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