Insurance cancelled but still debiting account

I have a complaint about National Security & Fire (Mafikeng). I cancelled the insurance in August 2021 but to date they are still debiting my bank account. I went to their offices several times to lodge a complaint but obviously they're not taking it seriously as they say even for November the debit is still gonna go through. I want this company to refund my money from August till now as soon as yesterday. They're such a useless bunch of *********** people.