Help with long term mobile issue

I have been working on a billing issue for over 1 month now. I have talked to 5 different C.S. people each one says they fixed it then want me to fill our the survey. The problem has only gotten worse and more expensive. We have been overchaged by $657 and more and were creditied it once then charged it again. Please rectify this ASAP. I was supposed to get and email from tech support and have not gotten anything. THis is the absolute worst C.S> we will be moving on but need this handled the right way for the last time!