Good on you for taking it to Citizens Advice - was that the telephone helpline? I believe that's the new frontline for Trading Standards - so the serious complaints get passed on to Trading Standards. This sounds like a Trading Standards or Competition & Markets Authority issue (the CMA is the new OFT). Unfortunately you will never hear about it again - this is a massive flaw with their system, in that once you make a complaint, that's the last you hear of it again, whether or not they do anything with it. It's the opposite of transparency.