Treating Customers Unfairly

I bought a Cell C Summit phone in March 2017, in June 2017 it stopped working and its battery couldn't charge, I took it to the nearest shop for repairs in Howard Centre pinelands. The 1st thing that the consultant said was 'we've been receiving lot of complaints about this phone, anyway it’s a cheap phone that is not meant to last you for long, and my response was "but you are still advertising it knowing very well that its faulty & and it might be cheap to you but I still expect it to work". They sent it to their repairs centre and the feedback they receive was that it can’t be fixed and they must give me a new one, which they did. It’s now October 2017, 4 months later the phone I was given is giving me the same problem that the old one did, it does not charge.

Can somebody from Cell C tell me if advertising a faulty product and selling it to clients is 'Treating their customers fairly ' ? what irritates me the most is that they are still advertising and selling this phone knowing very well that it’s not functioning very well. A R999 may be a small amount to them but to me it’s a lot of money to pay for something that is not working, I want a full refund not another faulty phone.