Complaint Review: Warranty Service Center

This company continues to call our business 6 or more times daily. We are on the Do Not Call Registry, but they continue to call.
When I press the #1 button to speak with someone and start asking questions, they hang up on me.

The two most recent incidents happened on 2/16/09 and 2/17/09.
When I did reach someone on 2/16, I asked them to please take our name off of their list. The woman (at this time, I did not get her name) said "Oh, you were just waiting for this weren't you." She then hung up on me.
The next day on 2/17, I pressed the #1 button and asked the person to whom am I speaking with. She said, Mrs. Cummings. I asked for the name of the business and she then hung up on me.

I don't know what else to do to track these people down. The only name I keep coming up with is Warranty Service Center.

Very frustrating. Hope they get caught soon!

Aimee
Camden County, New Jersey
U.S.A.