Refusal to cancel land line

I called Telkom to cancel my account (landline).

The agent advised she can't do this as I must fill out a form and with a copy of my ID, email ********** which I did.

I firstly received an automatic response saying they got my request and that it would be processed in 21 working days (which in itself is ludicrously long and inefficient).

Shortly after I received an email saying my submission of documents wasn't accepted as they have no space in their inbox and I must email them again later with the cancellation request. This I have done about 4 times with no success.

It does seem Telkom are hellbent on not losing me as a customer and instead of offering me better prices and services resorts to ignoring cancellation requests so the billing continues. This is essentially theft.

Please respond with urgency Telkom.