Ridiculous Premium Increase

I received an email from Outsurance 3 weeks ago notifying me that my premium on a 2006 Hyundai Getz will be increased by TWENTY PERCENT from 01 January 2022. This is TOTALLY RIDICULOUS. Inflation is below 5% how can I as a pensioner be told to pay 20% more for a 15 year old car. I have sent FOUR emails in the past 3 weeks and had had NO RESPONSE from Outsurance. I eventually posted a complaint on their website and got a negative response informing me if I want to cancel my premium I can. This is so sad as I was happy with Outsurance BUT I am not willing to pay an additional 20% when my car is parked in a locked garage 80% of the time. As mentioned, I am a pensioner and don't travel much