over billed account

I signed a contract for a laptop which costed R224/pm and 3G data sick for R75/pm and insurance that costed R69. In total this amounts to R368.00, which is what I signed for and what i should have been paying for. Firstly the insurance was not activated at the time of signing and secondly I was over billed every month from June to August and double billed in September. I have visited the 4u store on 8 occasions which is a waste of my time and is pathetic service coming from Vodacom. Everything is correct on the part of the consultant that assisted me, but the problem comes in at the accounts department. I would like this matter to be treated as one of urgency, and would appreciate some feedback on the matter ASAP, as I am very unhappy and would like all money owing to me back and not credited to my Vodacom account.