ASSISTANCE TO CANCEL CONTRACT

I ordered a phone online from cell c on the 8th October 2015 finally the phone was delivered 3 weeks later on the 22 October 2015, but only to find that the phone delivered wasn't the phone i wanted, when i inquired from the sales rep i liaised with to get the phone,he advised that i can send back the phone and cancel the contract since i don't qualify for the initial phone i wanted.Now i cant seem to get anyone to assist me with cancelling the contract and taking back the phone, I've been trying to contact the call center on 084145 since last week Thursday with no luck. i then decided to send a complaint via their website \contact us page"but still no luck.<br> Now my problem the sim card will be automatically activated and they i'll end up paying and using a phone i DON'T WANT!!!!"""