Unhappy with service

When insuring my new car. I gave the correct model was given over the phone. However the Consult entered the wrong MV details (the more expensive higher model). I was then contacted and the correct details captured. I was then told that the premiums will be more expensive now that the correct MV has been captured. When asking about why the premium was more the consultant proceeded to tell me that I gave the wrong details for the car and did not want to listen to me. I then had to over talk her and ask again firstly why she said I gave the wrong details and if it is a cheaper car why were my premiums more expensive. I was then put on hold for no reason and I had to cut the call after a few minutes. I think this is shocking service. I have been with Budget a long time and even though other insurers quoted me cheaper I still stuck with Budget. Can someone please explain why my premiums are more expensive with a cheaper MV.