Flying fish competition

I enteres their Saturday competition and i saw it wasn't fair. On the Saturday of the 11 March it was said that we comment in the hour given, which I did. However someone that entered after me won. And i called them up on this. Came the next Saturday, 18 March i entered again and this time i won. Guess what they did? They gave me an incorrect code. I sent them countless messages but till today no response. I used my data for all of this and i took my money for transport to Shoprite. I looked like a dumb person. That's humiliating to go to the store, pick the product, wait in line, only to be told the code doesn't work. Please assist further.