Discovery kids vitality active rewards - false advertising

Discovery kids vitality promotes health rewards for kids yet their rewards aren’t actually rewards. This is the third time I have redeemed a kids meal voucher for nandos. The first two times the vouchers didn’t work and it expired. I have messaged discovery for a refund as each voucher is valued at 350 discovery miles. To date nobody has responded. Today again I tried redeeming another voucher for my child. Discovery bills 350 miles equivalent to 35 rand for a 13 rand voucher. I had to pay in 36 rand for a FREE kiddies meal. That is just pathetic. So what motivation is this for the kids. It’s actually pure disappointment. Time to up your game vitality and stop *****ing from the kids