Unlock Summer is a ****. I never recieved my prize

On the 18th of November I won a prize with the vodacom Unlock summer competition. The prize was a R1000 towards my bill. I recieved a text that stated that a consultant will call me within working days. The 7 working days lapsed without a call. I later recieved a text that said that the R1000 will reflect on my next statement. Firstly I don't have a contract with vodacom I'm on pre-paid. So I've been wondering how will that happen. I tried calling the customer care line but it doesn't give an option to speak to a consultant. Now I'm just wonder if vodacom is running a **** or these prizes are legit.