Service disgust with DSTV (AGAIN & AGAIN)

Once again, horrific service from DSTV. I cancelled my DSTV months ago (DUE TO POOR SERVICE). Been with them for over 20 years and I must admit they have lost the plot. I cancelled telephonically giving them 30 days notice. They did not cancel and continued debiting my account. I called and enquired on numerous occasions. Eventually I spoke to a very rude women and she disconnected me immediately. They continued telling me I owe money and I spoke to numerous people and they eventually told me its sorted out an I took it for granted it was. Now I am getting mails from debt collectors saying I must pay. LOL what is going on with DSTV