Struggle to cancel Telkom account.

I cancelled my telkom ADSL line June 2018,gave a month notice and paid my month notice!! We are in November 2018 and it's not been cancelled yet. They still bill me each month, I phoned them every month July, August, September, October and going in November With a lot of reference numbers. Still not sorted!!!! Even went to stores, where i haven't succeed to cancel. Spoke to a manager who told me they can't cancel cause it's stuck in the system. I'm taking legal action against Telkom now!!!