Useless Sales Agents/Billing me for no reason

On the 11 Mar i app**** for a Cell C data contract with Mpho, i specified what i needed the sim for and told him i need a nano sim, on the 13th i received a micro sim, i immediately called back to let them know i received the wrong sim. they said the sim will be collected and i will receive a new one, i have been phoning leaving messages for Mpho, since he is soooo busy that he cannot return my calls or emails ever!!! on the 20th Mar i phoned and spoke to Calvin also in the sales department since Mpho was Yet AGAIN unavailable. Calvin said to me that he can help me and do the contract over and i can just cancel the old one when i get the new one since i didnt open or use the sim i wont be billed. fine. Today 24th Mar i decided to follow up since im used to their bad service, i called the cancellations department to cancel the old sim, the lady i spoke to says to me there is only one contract on my name so the new one doesnt show and if i cancel the old one i will be billed since it was activated, i explained that i did not even open the sim and i did call to report the wrong sim was delivered, so why the hell do i need to pay for something i did not EVER use!! switching to VODACOM