Debiting my account with no contract and installation: *********

I did a quotation with National Security around August/September 2019. I then told them I am not interested in their contract. There was no installation done for the alarm. To my surprise, they started debiting my account causing a lot of unpaid debit orders on my account. I called them in September, October and November to cancel the debit orders to no avail. They first insisted that my contract was in force despite no installation being done. They promised to cancel my contract but it's 6 months later they are still debiting my account. I need all the refunds for the unpaid debit orders and an apology of my credit record they will never be able to fix.