Sasko competition

I entered the Sasko "thanks SA" competition and won R50 airtime but up until today I am still waiting for the airtime. I have called the competition line at least 3 or 4 times and on the 3rd call was advised that the campaign manager would call me but no one did. I called again after that and was told that the campaign manager didn't send out the voucher's since my last call and that it will be sent later that evening. According to them I should have received the airtime already but I told them to call cell c and check if they do not believe me but they just said that it would sent to me.