replacement decorder not working

We have been without connection for 4 days and numerous calls to the call centre as well as visit to the Durban office has brought no resolution. ....we have racked up call bills over 2 hrs sitting the on the line with call centre and when we went to get the decoder changed came home plugged it in and had to call call centre told that the replacement decoder does not work......this is frustrating as we pay insurance and they do not give us a new replacement. ...how can they get away with such service....we pay astronomical subscription we run through the same things with the call centre agents..