Cancellation of a policy

I phoned Outsurance on 1/2/2018 to cancel my policy. I was asked for a reason, gave it and then was transferred to someone in sales. Then it became a very unpleasant experience. I again gave my reason for cancellation and my and it became an argument in which I finally lost my temper with the agent. Who the hell is she to tell my that I am making a bad decision for cancelling and haven't done my calculations correctly. I was eventually transferred to her manager. He then passionately argued that I shouldn't cancel and all I kept asking was what the process was to cancel. He had at his fingertips the years that I'd been a client, the amount that I'd paid to date as one of their clients, and how much I'd received in cash-back bonuses. He offered me a relatively big reduction in policy price and excesses. Why is this only accessible to us when there is an attempt to cancel. It is clear that Outsurance are happy to keep customers paying 'higher that what they should pay' premiums until they want to cancel, and then they tell you that you have the right to ask for review of premiums anytime. Pathetic way of trying to hold onto customers after they've taken years of over-payments. 25 minutes later at my phone cost, and the call still hadn't ended and I politely told the guy to just make sure my policy was cancelled - after I asked him no less than 3 times to confirm for me that the call was being recorded so that there is proof of cancellation. VERY FRUSTRATING AND ANNOYING