Telkom contract canceled without my knowledge and have to pay

I took a cellphone contract with telkom at the beginning of the year. Everything was well up until last week whether i discovered that the Telkom Sim card has no network. I called the contact center and i was told my contract is canceled by who they dont know and i never canceled any contract. I asked them to pull the recording for when it was canceled and they never provided me with any. Kept on calling them and they opened a case to investigate and it will take them 72hrs before resolved. Yesterday i received SMS stating my case is closed but they emailing me statement that i should pay for the cancelation of the contract. I called them like now and im told someone closed the case and the lady reopened another one and have to again wait for another 72hrs. I requested to speak with Manager or Team Leader but was told they dont have such. This is really bad service and remember month end the debit order went through but now i dont have network benefits.