Poor Service From Vodacom

I took out a contract about 3 months ago from Vodacom, the phone is faulty from day one. The phone has been with me for only 3 weeks in this 3 months period due to the fact that the phone have been in the repair centre most of the time. Vodacom is selling faulty products and they are not doing anything in this matter to solve the problem. Customer care Vodacom is referring me to the store where I took out the contract, the store is referring me to the repair centre. Vodacom is messing me around and yet the problem can't be resolved. In the meantime I'm paying for a phone that is no use to me. I'm so sick and tired of the poor service from vodacom