collect as much proof as you can and then "go public" with it to expose this issue. keep posting on twitter, relevant blogs, consumer advocacy websites, etc etc
and/or write a really good letter documenting your situation and do "executive email carpet bombing", in other words collect as many email addresses of management/execs/supervisors/public relations department as you can and email all of them at once. take a look at
http://consumerist.com/how-to/eecbs/ and
http://consumerist.com/how-to/execut...tomer-service/