poor service on account issues, pay me back

in january i hade a query on my account that was billed to me, 6900 , this is 2000 more than my original account. i queried the bill and was told it would take two weeks to investigate. it is now 45 days later. every time i call vodacom they send the account person a messAGE TO CALL, I CANT GET A DIRECT NUMBER!!!<br> yesterday i waited 12min to speak to someone i just hung up.