Double Insurance Charge on my Vehicle

I have both VAF and motor vehicle insurance with Standard Bank. I was charged Insurance double for my car for the month of August. Before the end of August I called Standard bank to enquire why is the installment for my VAF higher, and they advised that included in the installment is the insurance amount. I further asked that on the 1st of September they wouldn't debit my account and I was told not. Fast forward to today, I called in again during the past weeks and was advised that the insurance attached to my VAF is a Hollard vehicle finance that I did not sign up for. I was never today about this insurance policy and never consented to it! I have not received my refund and its now mid month September. I don't appreciate the service because, if I didn't have funds in my account and Standard bank had to debit my account, I would be charged exorbitant charges!! I want to make use of those funds. I kindly request for Standard Bank to do right by me.