Poor admin and not treating customers fairly!!

Good day I cancelled my account on the 10/08/2017. Received confirmation of this on the 15/10/ 2018. Recirved an invoice with negative balance of -R55. Then my bank account gets debited with an amount of R108.44 which was my normal subscription. I reversed the debit. Logged a case which no one responded to. Received a new bill on the 04/12/2018 saying that amount of R255 will be debited of my account on the 31/12/2108. Which never happened? Now i get a demand from a law firm that I owe over a R1000 which has gone up to R1300 in weeks time? How is this possible. There was not one phone call, email or sms from Telkom since the 04th of December 2018. Can someone please call me to answer the following questions? Is my account bill in arrears or day I pay upfront for usage? If there is a problem with my account why does telkom not contact me? Why is my account handed over to debt collectors firm with no contact from or notification from Telkom? Please contact me urgently regarding this .