Debit orders on bank accounts without consent

A couple of month back I searched for a new insurance to try and save on my premium. Miway gave me a quote where I have stated that I will look at it when I have time and arranged that they must call me the week after to discuss what I've decided. The next week I told them that I will be staying with my old insurance as I received a better quote. Since then I have had debit orders added to my account after telling them I will not use them, and for some reason they even had my old bank account and added debit orders there as well now as of this month, even after calling them 2 or 3 months in a row to stop with the debit orders. No one is listening and this is aggrevating. I have no idea what to do anymore. There is things going on in this company which is troubling to say at least.