Honor and mtn false advertising

Honor promised me a pick and pay voucher when taking a contract with them on MTN but it's now a month later and when I ask them on their support channel they tell me that I don't qualify for it and that the batch of vouchers have run out. One of the things that motivated me to buy their device is that voucher apart from its features. They are false advertising and coerce people to buy they products and don't deliver.