Unreachable customer service.

I requested a cancelation a month ago. I received an email stating my services will be canceled on the 30th of July. Today is the 1st of August and my service has not been canceled. I cannot start my new service with my new ISP until supersonic releases my line and it is near impossible to get through to customer service to request the release of my line. I have wasted hundreds of rand in airtime trying to call these useless people over and over again to no avail. I just want my line released please.