Poorest Service I have ever experienced in my life

There has been identity theft I don't know how they got my details to open up an account under my name and now I have a bad credit reference furthermore they don't want to even give me a Letter of no interest and the car I want to buy the special has now finished and I missed it all because of them up until now they still investigating by their words. Absolutely Poorest Service I've ever received in my life and I am not even a customer of theirs I wonder how they treat them.