Telkom Service Delivery :-(

I have been trying to cancell my wifi connection since April of 2019 but I am being sent from one department to the other. I have emailed my cancellation document but with no avail. Thus I have unplugged my router since then and left it unattended, now I receive a call from a company stating I have been handed over due to the outstanding balance of my account from Telkom, the same one I have not been using since April. I still do not get any answers from Telkom offices but I need to be punished for them not giving service delivery. Any advise on how to handle the situation?