Bad service from Absa Idirect after cancelling and deducting money from my account.

I had a car insurance policy with Idirect and I cancelled the policy due to the the high premium, spoke with them and also received confirmation that that the policy is cancelled, but to my suprise they debited my account and they are not not willing to refund me, I have been calling and writing several emails but they are not responding. What a **** of an insurance company which is bitter that no longer want their service which is very expensive.