Incorrect data captured

Had a bad experience a few days ago. I was contacted by OUTsurance for a quotation and if the could not beat my current premium they would pay R800 to me. I accepted the quote because it was similar to what I was currently paying. Upon receiving the policy documents I noticed that the details of the car was captured incorrectly. The salesman entered it incorrectly and this resulted in me having to call back and change it. I did just that and the premium pushed up to almost R200 more. I was very disappointed because had I known this in the first place I would not have accepted the offer. I had enquired about this and was told there is nothing they could do to the premium. My issue is that they have no sympathy for me having to find a different insurer now and being charged the once off fee payable as well. My question is now seeing that they could not actually beat my premium is the cash back promotion not due to me any longer?