I joined the car insurance with Auto and General in 2014 but even though I have been with them for that long, they are still increasing my premium yearly but the car price has depreciated and no fairness on castomer loyalty

I joined the car insurance with Auto and General in 2014 but even though I have been with them for that long, they are still increasing my premium yearly but the car price has depreciated and no fairness on castomer loyalty. I was hoping to to be paying at least around R1500 per month by now not more than that, they decided to increase my premium at the end of June by a very high rate without even giving me a caretecy call to inform me of such change. So now when I inquire and asked to have my policy reviewed they told me that they can only come down to around R2000 but what is this really? I don't understand....