6 phones in 8 months

I bought a new iPhone 6 plus, through, Vodacom, less than a year ago. They have replaced or serviced the phone 6 times leaving me without a phone for approximately 2 months in total. Once providing me with a R500 phone as a \ courtesy\". I have been so desperate that I went out and bought a \"backup \" phone. I have pleaded with them to supply me with an iPhone 6, which is significantly cheaper, but I would not insist on a credit. They told me it was not possible due to company policy. It has now gone in for the 6th time. I do realise that Apple is a profit driven company, but surely they could at least supply me with one of their cheaper phones, as long as it works. Vodacom has been no better. Their manager never returns my calls. "