Telkom harassing elderly for R400

In 2018 our ADSL line stopped working. We contacted Telkom and they came out about 8 times to "fix" it. The last person told us that there is one port missing and they would put our line in, then when the next house complains about adsl being off, just take out our line and insert that line. This interrupted our service constantly. So we went with LTE from another service provider and cancelled the Telkom contract. This meant signing up online, and cancelling everything online, since humans does not work there anymore. After 2 months they were still charging us for the service, even though the landline was off and the adsl stopped working 4 months prior. We refused to pay the R418 invoice. This year they started hounding the account holder, my 79 year old father, for the money and even gave it over for a collection agency. The fact that they never solved our problems, do not have humans to talk to, outsource service calls and cannot escalate problems, does not factor into their greed for the R418. With aging parents that have problems with service providers, I find that they discriminate against the elderly that cannot understand their technical mumbo-jumbo and if I try to help they "can only speak to the account holder".