VERY BAD SERVICE

I did an upgrade in December 2015, i received my new handset on the 7th December. My handset was faulty and eventually i took in at Midrand repair centre on the 13th January 2016. The warranty assessment was done in an hour, i was told to contact MTN Direct so that they can issue me with a replacement handset. I have been calling the 083 123 337 number and i think i have spoken to almost every other consultant in there. To date i dont even know when i am getting a new handset or if that will ever happen. its been more than 7 days i am without a phone and i am not getting any feedback from anyone. My REF ***, REF ***, REF ALWIC ***, i need to cancel this contract