Refuses to cancel my insurance

I’m really crossed with Bidvest insurance, I took tyre insurance for my bakkie when it was time for them to pay for my claim the gave me problems, they never paid until I decided to cancel the insurance, however they are still debiting on my account, they don’t wanna cancel the policy every time I call they tell me they’re transferring to the right department, and they never pick up my calls, how can I stop this *****ulent from happening, it’s been 2 months now trying please help.