TELKOM's administration is despicable

I cancelled a landline and ADSL line on behalf of my mother, who has dementia. All the paperwork were submitted to Telkom in January 2018 and we got a notification that the service will be suspended at the end of January 2018, which duly happened, BUT they still bill my mother for this service. She has a landline at the retirement village where she resides and is billed for this PLUS the terminated land line and ADSL line. I phoned on several occasions and the standard answer is that there is a backlog. How do they expect an elderly lady, who lives on a fixed income, can afford this? It is 6 months later and still no progress...