CAB would be my first point of call but from personal experiences they are usually as useful as herpes at a gangbang. I would try and seek independant legal advice, most solicitors will offer their time for a short period and valuable knowledge free of charge and some may even go further for you.

You could also try trading standards, at the end of the day they are here as a service and a regulator so they should offer you some good advice.

Failing that jump up and down, throw your toys out the pram and shit the bed in protest until they back down.

Relatively speaking my last suggestion is nearly as crap as my others.

HTH
Tim