Charged more than I was quoted

Good day, I thought that the initial problems with my current cellphone contact's been resolved until I got this month's invoice. I was quoted only R200 per month for a Flexi200 contract which I agreed on when Chrystal from Mondo phoned me at 1st. I was told that I would not be charged for the handset like I would have if I had gone into a local Vodacom store for my upgrade. Yet I now see that I am billed for a 24 month handset installment of R30 per month PLUS a Vodacom screen insurance of R79.99 which I was not informed about. Please advise. <br> Erika Sissison