Telkom black listing

I have cancelled my services in February 2018. I have been given 3 case numbers in the last 3 months, telling me you are working on the problem. I have been in the store twice now, trying to get HELP! Every month you deduct money from my account, for services that you already stopped! What makes it worse, is that on Sunday I get a message that I have, once again, have a new case number, and on Monday I get a message threatening me, if I do not pay you are going to black list me???

Dear Telkom,

I do not give you permission to take money from my account. This is ********l, and put simply, robbing!

You, as a company, owe me!