The Qatar airways cancellation policy is within 24 hours only if you have booked directly through the airline or its website. Also, you can opt for refundable tickets; it might be a good idea to avoid the unnecessary hassles of cancellation.
Passengers are allowed to cancel their tickets within 24 hours of booking. In this way, they don’t have to pay any charges for it.
But in case the flight has been canceled or delayed then you can surely ask for a refund.
Qatar Airways allow you to cancel or modify the booking to or from the US within 24 hours without any payment. But, once payment is received and the ticket is issued, standard fare rules will apply. https://www.airlineticketpolicy.com/cancellation/how-to-cancel-qatar-airways-flight-ticket/