Difficulties with King Price policy cancellation

I have been let down by King Price twice. Firstly my car broke down in a very dangerous place with a lot of luggage on it and I asked for their towing service which arrived after 9 hrs. Before, they all along assured me that help was on the way. I was escorted by Police until their breakdown truck arrived later. Secondly, I have been with them for a year now without a single claim. They temporarily lowered the monthly premium by R35 and to my surprise, later in the year, they suddenly inflated the monthly premium by R74 which indicated that they were recovering funds from reduced premium. On paper, they always claim their reduced premiums. I then contacted them to cancel this policy. On numerous occasions, I found that once the reception puts you through to the Cancellation department, you will get a response from the person talking to you that he can't hear you. He goes on like "Hello, hello, I can't hear you, there's a problem with the line" . I tried a few times again, coming across different voices most of the time. The same thing happened for several days. I then sent an angry email and response from them came back that they have been trying to get hold of me and without contact with them the policy will remain active. I asked the bank and advised me to block their debit details if they don't want to heed my demand. That's what I now intend doing otherwise when it comes to policy cancellation, they don't want to know.