ThankYou terms are ambiguous.
In one paragraph they stipulate that
all tickets are non-refundable:
All airline tickets, hotel, car rental, vacation packages, cruises and activities booked in exchange for ThankYou Points are nonrefundable, nonendorsable and nontransferable. Changes to bookings are subject to the fees and conditions described in these terms and conditions. All changes must be within the same travel region as defined by the carrier's fare rules and meet the booking requirements in effect at the time of the change. Any additional costs due to a permitted change are your responsibility and will be collected in U.S. dollars, not ThankYou Points, with a credit or debit card in the name of the ThankYou Member. Any change, cancellation or additional collection fees imposed by the airline, hotel, car rental company, tour, cruise or activity provider are the responsibility of the traveler.
Yet in another paragraph they stipulate the fees for processing refunds:
Airline tickets are NON-REFUNDABLE and NON-CHANGEABLE unless permitted by the terms of the fare and are subject to airline rules, penalties and fare difference. A $35.00 per ticket service fee for domestic flights and $50.00 per ticket service fee for international flights will be collected by CLTS for all exchanges, modifications, or cancellations, in addition to airline penalties and fare difference. CLTS fee(s) will appear on your card statement as Trip Charges.