Sub standard phone

As per my complaint logged the 18th of April, Cell C contacted me on the 20th. I took the phone to Cell C, Lakeside, Benoni on the 24th of April 2015. They contacted me on the 11th of May to collect my phone. On collection the 13th of May, Daniel informed me that the phone is unrepairable. As I will be due for an upgrade in only a year's time I have to pay for a contract phone that I don't have. As this is the second phone in a one year period, I seriously think they sold me a sub standard Blackberry phone. I expect nothing less than a new phone that will, at least last for the remaining year.