MTN doesn't want to cancel my contract that expired in 2016, they keep deducting money from my account

MTN is requesting to keep paying monies each time i want to cancel a contract that expired in 2016, i want my money back. I have been requested to pay R400 for cancelling the contract on the 9th of September and was promosed the contract would be cancelled in 24 hours, but nothing was done. Instead they loaded some more data and was told the contract still stands. I need my money back. Today i was again asked to pay another R150 to cancel.