When,when,will they fix my phone and internet

For the last three months on numerous occasions I called Telkom to look at my scratchy landline with intermittent internet facilitiy. A technician arrived to say that I need a Potts filter and my problems will all vanish. I collected one at the Kenilworth Telkom branch, thankfully free of charge. I then connected it and found nothing changed. I called again to log a call for Telkom to visit. Could you believe it, two weeks down the line and nobody appeared. Is this the kind of service one can expect as I am paying for a service which I cannot use. Now this is not only frustrating but also a financial loss. Telkom you are pathetic as a service provider.