There will be a number associated with the card (probably printed on the back) to ring and one of the options will be to book your free flight. These expire after 12 months so get in there soon play dumb and you MAY still get your first flight.
You've probably missed out on your first flight though - but try and sweet talk them into giving you two this year.
Call the Customer Support number on the back of the card for details on the flights, or refer to the brochure you got when you first got the card as to the routes.
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