False advertising. The vouchers are a lie

I app**** for a contract online and got approved for the deal. Its a Huawei 12i with ear pods and the deal included a R500 pnp voucher and R500 Huawei voucher.

I received the phone but heard nothing regarding the vouchers. I contacted the Mtn team via email and got passed around. I went into the store and was told they can't assist online customers but told me how to do the QR code on my phone for the Huawei voucher And not pnp. I then got home and used the QR code only to see it expired. Till this date I haven't received any response for vouchers that is owed to me. This is false advertising and I would have rather stayed with Cell c instead of being messed about with a company that draws in customers but lacks the service they offer.