Merchant Services, Inc. fraud! Rip-off! Plainview New York

I received a phone call from a David Harris, stating he was from my merchant credit card company, and would like to come in to see me. When we met he told me that he could lower my discount rates and give me a new credit card machine. A few weeks later I noticed that I was being billed by two merchant credit card services.
I immediatley called Mr. Harris to rectify this billing error. At this time he told me not to worry he would take care of it.

In the mean time he showed up at my place of business, and put in a new machine, taking my other machine without my presents. As months go by, I am still being double billed. I contacted Mr. Harris, and he agreed to see me. Mr. Harris told me he was going to send me checks for the double billing each month. A few more months go by without any payment, so I try to contact Mr. Harris and find that his phone number is disconneted. I than contact his company Merchant Services to get in touch with Mr. Harris, and they tell me that they have no phone number on him, but he still works there.

I call Merchant Services again, and filed a complaint against Mr. Harris. They tell me that someone from their company would call me back. Weeks go by and I have not heard from Merchant Services, so I called again.
This time when I call them they tell me that there is nothing they can do. I than ask for a sales manager to speak with, and they tell me he cannot help me neither.
I now have hit a brick wall, and do not know where to go from here.

Janet
Howell, New Jersey
U.S.A.