You should keep the following in mind to know about the cancellation policy:
If you cancel your ticket within 24 hours of purchase, you will not have to pay anything extra, you will get a full refund.
If you cancel your ticket after 24 hours and within 7 days, you will have to pay $99 and the balance will be refunded.
Sun Country Airlines refund and/or cancellation depending on the fare type chosen. If you want a refund on your ticket, you must complete the cancellation policy.
How to cancel a Sun Country Airlines flight online?
Call at +1-888-566-5066 or read here: Sun Country Cancellation