UNRELIABLE & INCORRECT INFO

I phoned the call centre to find out when my contract will end & I was told it was the end of Feb 15. Then I sent a cancellation form that I no longer wish to subscribe for a contract service as at 1 Mar 15. I received a email from retention dept saying someone will be in contact with me. No one phoned. I have been converted to prepaid but I received a bill in April for R688! Migration charges & migration penalty. This is when one upgrades a contract! Now the call centre says the issue is with the billings dept. I have not budgeted for this cost, for which Telkom has made the error! I need this reversed immediately.