Telkom Terrible Service

My contract expired for the second time now (4 years) , telkom still keep debiting my account with strange amounts,this is ***** as the amounts are never the same, my initial contract was R130 a month now they taking R350, is this legal as I have not authorized it? I have tried to cancel my contract and was always given the run around, even tried online service to cancel, the system does not recognize my email but i get emails from Telkom no reply when payment is reversed, that is the only time they communicate, Went to Maponya Mall Telkom and was assisted by Lebo (lady) who told me to come back after a month which I did, got a different lady who then told me I need to come back in 2 weeks, I really did not have the time to go back and to this day I still have an unsigned contract with Telkom, how I do not know?? Very disappointing service all round, Still waiting for an agent to give me a call after I completed their online contact form.