Netstar tracker terrible service

I am at the end of my rope with Netstar. My tracker has been inactive since October 2022, I have called every month for the last 4 months and no one has come out to fix it. I then tried to cancel the contract and they tell me I have to pay a huge cancellation fee, for the worst service I have ever received. Then I am randomly debited by them over and above my premium. I have had enough and logged a complaint with my car insurance. I want out and with no payments and I want my payments since October 2022 to be refunded!