handset device exchange not successful

Cell C called me to notify me that I qualify for an upgrade, I asked for a blackberry device but a different device was delivered (Microsoft) 06/10/2015. I called in today to arrange the device to be collected and changed and I'm told about the 7 days calendar notice which was never explained to me nor was documented. Every time I call 084 143 and being put through to the department they just hang-up on me without any assistance. My issue here is that the device received is not user friendly as I'm not too technical with this new technology, all I'm asking for is a simple, user friendly device that I can use. I have not nor can use this device. Can somebody please assist in this matter as I'm required to pay monthly fees for a device that I cannot use.