Cancelled cellphone contract still being charged.

on the 31st December 2014 i spoke to a lady called Celina in your cancellations dept to cancel my cellphone contract which was reaching its two years. She took down all my details and confirmed that my contract will end on the 31st of January 2015 and the number will then be changed to Prepaid as I asked. Now on the 1st of March I got debited by Vodacom for the same cell number, when I called the cancellations dept I was told that Celina did not complete the process so I'm actually still binding to a contract. I am NOT prepared to pay anymore payments to Vodacom because their staff is incompitant and can't do their work. I want this number on pay as you go and I will not pay any further monthly debits. It would be appreciated if this matter could be resolved as I have tried to call Vodacom for 3 days now and no one seems to be able to help me. I have spoken to Lesego and Sibisio today again but have had no help as they say I need to speak to the people in Midrand. They tried to transfer me to Midrand whilst I was waiting and kept on getting cut off. I refuse to waste more time holding for Vodacom and their ***********, unskilled and unwilling staff.