Chuck, if you have ever called back on any of the scammers' numbers, you did opt in. They have a record of YOU calling THEM.. which establishes a previous business relationship. Never call these numbers back to see what they want. If it's really some one trying to contact you, they will leave a message.
Just another one of the constant stream of scam calls. Really doesn't matter whether you block the calls, answer them, or call them back. NOTHING stops them from calling- even if you NEVER answer your phone.
I'm sure pleased I have caller ID !!! 253-216-2526 plus 253-455-7298 don't care if your on the " do not call registry". I wish there was a way to stop these calls.