Wrong Takealot voucher code

Hello I have a huge problem with vodacom that cant seem to keep their promise and are very unfair and disloyal. I won a competition with my friend 11/01/18 we where requested to DM our contacts and address. We did that. So now the problem started when they emailed us invalid takealot voucher codes with 12 characters of which should be 20 characters. I told them about it, they sent me another wrong code. I asked Takealot to give me an example of their voucher code so i can show vodacom. I then emailed vodacom how many characters should be there. They then continued sending me wrong invalid codes with 12 characters. They continued sending me those codes and i kept telling them they are wrong with the proof. They then stopped responding to my emails. I think thats very unfair to me and my friend. I have screenshots of everything as proof.