Gross Incompetence and failure to remedy problem

I app**** for a Telkom Smarthome Advance package, which was (finally) activated in January this year. However, instead of providing the 20GB internet cap that goes with the package, I am receiving only 10GB every month since. This problem is apparent from the Usage Tracker tool that Telkom provides and has also been verified by every Telkom agent I have spoken to. However, despite numerous calls to the Telkom call centre as well as a visit to the Telkom shop, no one has rectified the problem! I have reference numbers for the calls I made, as well as reference numbers for the escalation of the issue. After persistence, I even received the direct line number of one of the supervisors in Cape Town, who promised to resolve the issue. But Alas! In the true Telkom spirit of gross incompetence, he has also failed. Why am I being made to pay for something I am not receiving? To make it worse, it takes ****erally) a half hour or more before anyone answers at the Call Centre