Got a call from this number, they did not leave a message. I called the number back and the recording says: "To be removed from our list, please enter your 10-digit phone number, area code first." There is no mention of who these people are or why they are calling. If you wait past the message, eventually it just hangs up on you. There is no way that I have found to talk to an actual person.
I just put myself on the do not call list. Hopefully they will not continue.