MiWay -30% increase in premium . Disgusting

I have been a customer of MiWay for a few years now and have generally had pretty good experiences with them. Affordable premiums, acceptable excess and generally good customer service. Until now. I received my latest policy changes documentation only to find that 1. They made an error on the base premium on which they base the new premium. And 2) My new premium reflects a 30% increase in one calendar year. I contacted their retention department only to be told that there is nothing they could do and that I just had to stomach the increase. Disgraceful and disgusting given the economic climate to enforce that kind of increase. They should be ashamed.