Telkom overcharge still unresolved for over a year

Hi, September 2017 last year i downgraded my adsl uncapped 4 mb line to an unlimited to an Unlimited home 4mb package. Therafter Telkom continued to double charge me for the 4mb adsl line. A year later, phone calls every month since( average duration of an 1hr), empty promises of it being resolved etc Escalations to the sales and billing deaprtment supervisors/managers. Still unresolved.

Poor and unprofessional customer expierance. I trust that they will rectify their incompetence and reverse all charges immediately.