Call Telkom to wreck your day and credit record.

I had a Telkom line that I cancelled on 2018.09.28 ( ********** 6). I received a cancellation confirmation on the 2018.10.22 ( ********** 21A) that the line will be cancelled on 2018.10.28. In november I received a New invoice for November and December the same. January I received a statement showing my account in arrears and again now in February. Every time I receive an invoice I phone to try and sort this out. Yesterday, I received a notification that I have now been flagged for non payment and this reflects on my credit record which in turn has caused the bank to refuse me a loan I app**** for. I phoned again yesterday to try and resolve and was assured that the account has now been closed and a credit has been passed to show 0 balance. Today I receive an Invoice with interest. I tried to phone today only to be hung up on several times by the agents. They agent I dealt with refuse to help because on their system it says that the account is cancelled. I then ask for proof of this and they say that they cannot give this to me. This is ridiculous. they are now affecting my financial position and they think this is a big joke. What am I left to do...