Renewcontract without consent

I come from the mtn store they advised me to contact 809 I have been doing that since last week. I.I phoned the number 809 in March i spoke to a lady she confirmed that my contract will be cancelled as from 31st march 2015 and the number will be prepaid , however she did not do that she rather went and increase my monthly limit and the contract is still open... The 809 number is not working for me to contact them i need this contract cancelled and i want them to take back their airtime i'm not going to pay for it. They need to pull the call recording and see who i spoke to, That lady will be responsible for any funds because she confirmed it will be cancelled i phoned from *** ..I\m sure there must be customer notes or Customer remarks to see who last spoke to me .... <br> <br> "