Perhaps I can give some advice about making a successful complaint. Do it in writing , either as letter or email.
First of all, keep it short and to the point. Just describe the problem you are having. No emotion, no accusations and no threats. (Don't say things like "The fools Just ignore me.... fobbed me off.... if it's not sorted m leaving... and they can sue me")
Then say what you want the company to do. Try to stick to the point, be polite but firm. Now the important bit, either give someone else the complaint to check it makes sense and correct any little spelling errors or save it and come back to it later (so you can check it yourself).
Make sure you send or email the complaint to the correct person. Once its gone, don't badger them for a response. It can take time for people to look into your complaint. Allow about a week for an initial response which should tell you how long to wait for a full answer.