frontier airlines allows cancellations with full refunds within 24 hours of booking, provided your departure is at least two days away or (US). For non-refundable tickets, you can make changes or cancel without a fee, but you will receive a travel credit instead of a refund. https://support.dhigroup.com/forums/general-discussion/b3c4e565-88b1-ef11-95f5-7c1e52119dc3