Charged for fixed line for a year after cancellation.

I followed procedure and put in a cancellation request for my fixed line service last year on the 27th of March because I was going to be moving to another apartment at the beginning of May. I followed up on the 29th and they had no record of my cancellation form getting submitted, so I submitted another request to the same email and made my payments for April as usual. I was contacted in may to make a payment in may because that was the closing balance or fee, which I made and there has been no contact ever since and no feedback on refunding me my deposit. Today i was contacted by debt collectors claiming I owed R1,800 for my fixed line which I apparently have not paid for over a year. A fixed line I had cancelled. I have tried contacting Telkom and they are not picking up. So glad i manged to successfully cancel the other products last year, I would never recommend telkom to anyone.