DISGUSTING SERVICE

So i get a new contract from MTN and i clearly asked them that i would like to keep my number. To my surprise after the goods were delivered i was informed that because the number was activated , i will have to use the new number which was allocated to me. This was after my clear instruction that i have asked to keep my OLD number. OHHH .. that is not all. Now when i want to cancel the contract I'm being send from pillar to post . I'm being told the contract was sold to me by an outside company which is working for MTN.!!!!!!. What the hell? How is that my business?? PLEASE CANCELL THE SIMCARD NOW.