unsatisfied with organisation of winners prizes

I won a competition that was in december. i was told i will receive feedback from hi sense with further details. i was phoned once and not again. i eventually contacted makro head office and asked about my prize and was told that hi sense is struggling with the couriers and they have a dead line to deliver by 6 march 2015. if they do not then i will receive a voucher to the prize value with a bit extra for incentive. on monday 9 march 2015 i phoned makro to inform i did not receive anything from hi sense and miraculasly my prize arrrived later that afternoon. i wanted to refuese it as it was past the due date but gave them benefit of the doubt and accepted it. once opened one of the products were missing. when i phoned this morning is was told that they are aware of it and hi sense has until the 13th to deliver or once again i am promised a voucher. i informed makro that this time i am not going to accept the last item if it is late. i am not pleased as their word is not kept to as they say.