Insurance premium increase of +-40%

My building insurance on my house has increased premiums by 40%. It has gone from R5000+- to R7000+- per year how is it possible for a 40% inscrease when I had one claim where my excess was more than the contractors fee.

I queried this with absa but recieved a response back basicly saying I can not "yet" negotiate premiums.

This is insane I use to pay +- R3000 per year with a previous insurer on the same building now absa comes with this!!