TELKOM BILLING ME FOR CANCELLED ADSL LINE

I cancelled the 4MB ADSL line on 17 March 2015 because it never worked (always slower than 2MB). Ref nr. ***A. I checked the line on the 18th of March and it was down because it was cancelled. I'm STILL being billed now owing Telkom R1333 for NO LINE. In April I logged 2 disputes (for April's bill) on telkom's website and called again and asked to make sure that the account is closed. LOOKS LIKE NOTHING WAS DONE, ABSOLUTELY F@CK ALL. Just received a new bill from Telkom again for May 2015. *******ion, ***** NO ONE IS HELPING *** TELKOM ***FFFF!!!?!?!?!?!?!