Promises made and not kept

I was part of the takealot campaign and was given vouchers which expired even though I was told they do not expire. This was in June/July 2017. I raised it with Discovery and they have made promises to compensate me in the form of other vouchers since August last year. These promises are never kept. I am told they will mail them to me by x date, I never receive them. Neither am I informed that I won't be receiving them. Each time (and there have been many) I have to follow up and ask where they are. It is shocking customer service, blatantly dishonest and reflects poorly on Discovery. I don't think I want to have a relationship with a dishonest and unreliable company. I have already cancelled my medical aid and am considering cancelling my credit card and pulling out my investment. I have been with discovery for the past 10 years and this is how you treat loyal customers. Pathetic. Don't make promises you cannot keep!