Bad service from Telkom accounts department & my contract is cancelled but still being charged

I had a mobile data contract with Telkom which i cancelled mid September 2017 i was informed by the agent handling the cancellation that the contract will be terminated latest 23rd of October 2017, and i had paid a deposit of R1400 which i should get back once the contracted is terminated. End of October i received a bill of 1699 from Telkom though i had already paid for October, i contacted the account department on several occasions and kept on being transferred from post to pillar for 3 weeks, mid November i got another statement totaled 699 which will be deducted from my bank account on December the 4th. I went to a Telkom branch, they escalated the issue, i spoke to an agent who confirmed contract cancellation on the 9th of October, she also advised that i have voice over IP enabled which explains the extra charges, even though i never had such for the duration of my contract and router has been off since end of October, i never got my deposit R1400 back, 1699 was taken from my account and looks like another 699 will be deducted comes the 4th of December, i was given a reference number and never got a call back to this day, i do not know what else to do.