If you do not wish to travel, you must cancel your booking at least 24 hours prior to scheduled departure of the flight to be eligible for a refund. Spirit Airlines allow free changes and Cancellation Policy to booking given they're made within 24 hours of the booking. Travelers cancel their flight ticket within 24 hours of booking and receive a full refund - flight departs 7 days later.
Spirit Airlines Baggage Fees and Policy and allowance (2022) | How to check in online Spirit Airlines Flight |