Bidvest Insurance deducting money for a Car that i no longer have

Policy number: C-***

Initially i thought the insurance was Absa , i am very sorry , and thankfull that they are the once who picked that the insurance company is actually Bidvest. i have since changed the car and bought a different car but , they are not assisting . they are refusing to cancel my policy and also refusing to refund me for the 2 months that was no longer with the car and yet they deducted. from the look of things , it seems like they will forever be deducting my money for a car that i no longer have. how can i get to have this policy cancelled and aldo get my money back