Switched On sent me aVoucher without a Voucher and kept quiet

I did a survey a while back and won a voucher for R80, I then decided to purchase a KFC voucher on 30 July, I was sent an email on the 5th of august claiming that the voucher was sent to y cell number which wasn't. I emailed them explaining my problem but until now I have not heard anything, I also purchased airtime and am afraid they will claim they sent to me as they did. At this point, I am not sure if they are scammers or not.