Fed up with Telkom

Absolutely disgusted by the lack of service I have been receiving from Telkom. I have changed banks and in spite of me giving them a month's notice and giving them my new details, the still tried to debit my old account. I have back and forth for the last month trying to resolve this, but have not had any luck. I have explained to them numerous times that I am not responsible for the R202.70 for the debit that bounced. I've given them enough notice, but their lack of service has left my account in arrears.

I am just so fed up and it seems like no one at Telkom is willing to assist. I don't know what to do anymore!