battling with MTN over a year no help whatsoever ! ********** upgrade !

I took out a contract in 2015 , the contract was upgraded without my knowledge in January 2017, I have called endless times I have been in store and still no help, MTN is still charging me for this contract. I have been posted from department to department with no assistance whatsoever !!! it is so frustrating as the service is utterly pathetic! my documents were sent through and given in store , I have over 8 different reference numbers, can MTN please sort this out immediately as i have reached my level of patience with MTN!!!