FAULTY NEW PHONE AND POOR SERVICE

I was due for an upgrade in October 2015 and I kept receiving phone calls from a 021 number (wanting me to upgrade over the phone). I upgraded and the phone was delivered to my workplace on 30 November 2015. On 2 December the phone was overheating, freezing, once switched off it wouldn't come back on and I took it to a telkom store in Pavillion, Durban. The store refused to assist as I was told that I got the phone from a subcontractor-Sell Direct and I need to contact them myself. I called them and they collected the phone and said it would be ready within 10 days. Phone was collected on the 8th of December 2015, until today I still don't have a phone and nobody wants to be accountable. I'm sent back and forth between sell direct and telkom mobile, as far as I'm concerned I have a contract with Telkom Mobile and not with their third party (Sell Direct). I've lodged more than 5 cases in one month with no resolution to my case. I want to terminate my contract but I'm told that I will be liable for penalties for a phone I don't have. Call center cannot help me and I've had it with this company. No one wants to account and my bill has a data add on which I did not sign up for.