Samsung's flawed voucher redemption process

Samsung has a summer promotion icw Telkom for the S23 Fe and were giving vouchers for Flysafair, Uber , PicknPay etc. I bought 3 devices and tried booking with Flysafair only to be told I required voucher pins and was directed to Samsung as the Telkom agent also said I must check with Samsung. After to and from emails, I was notified that I was supposed to book the tickets using a third party called TLCtravels. My dispute lies in the fact that it was not mentioned during the redemption process to book tickets. I have already booked those tickets directly with Flysafair and requested the vouchers to be switched to any of the other products in Uber, PicknPay etc. Although it is an error on their side ,they refused to give me the benefit of doubt for switching the vouchers as they pointed out the Ts and Cs. They refused to acknowledge their mistake and advised that it will be forfeited if not used within 9 months. This is an unfair decision to leave me out of pocket and not give the customer the benefit. What are your thoughts?