I have been flooded with calls from them, too. My caller ID says, "Distribution." NO matter how many I've asked them to stop calling, they keep doing it anyway. I have reported them to the folks that take care of "the do NO NOT call" list, and that didn't do any good either. I wish you good luck with them.
You do realize don't you that the DNC is a Database, both for honest business to use and the complaints that are available to all agency's? You can file more direct with the FTC & FCC. Do consider maybe getting a call blocking device or phone.. You can google them and many are around $60.00 or so.