MTN South Africa misleading adverti*****t.

I was doing my upgrade with MTN. The advert were saying if you take this Fone you will receive a R600 Huawei online and a R300 Pick a Pay voucher. When you receive the Fone, you must scan the QR code in the leaflet. Which I did, fill in the form and attach the invoice, submit my form. Got my response which says it will take up to 5 working days to process my form. It's now 2 weeks from the day I submitted my form didn't receive any vouchers, didn't hear anything from MTN if there is something wrong with my form. So, I called MTN about this query now they can't help me I must my now call a company called Mondo Mindo Telkom. They must help me now. My problem is MTN advertise this deal but now they can't assist me to get the vouchers.