Failure to rectify billing , Failure to attend to case number lodged in this regard.

Despite lodging a case on 6 Febuary to rectify incorect billing , i was told my case rectified only to recieve my new bill showing that indeed it has not been rectified. (original case no ********** 4) I proceeded to lodge a new case ( ********** 3) in regards to the incorect billing. Three weeks have now passed and my cased still not attended to. I have called three different billing representatives this past week only to be told all they can do is to esculate as to why it has not been attended to.