Dissatisfied Loyal client

I received a call from one of the vodacom consultants in September to upgrade four (4) of my simcard which were due for a upgrade. I completed the contract over the phone with stipulations that one Simcard was for airtime of R165, the other for data of 20gig, a router for 20gig and the airtime that will remain R125. The total was about R800 for all the additions. I called in for this to be sorted out and my calls were transferred aimlessly from one consultant to another. One even gave a lecture on how minutes work and none of them wanted to assist or take liability for the issue to be sorted. The data is too much and the total contract now amounts to R1300 which is an amount not agreed upon. I still do not have a solution currently and no one can give me answers or sort out this mess.