559-321-0580 calls me at least twice a day. It has a recorded message that says for me to please hold the line for some very important information (or something to that effect). If I stay on the line, no one ever comes on to tell me what this "important information" is. I think it's a robo-call to see if a live person answered because I usually get other calls shortly after that from various telemarketers, usually solar companies. Yes, I'm on the Do-Not-Call list and have been for years. I wish the FCC or the FTC would enforce their own rules and stop this practice.
On the good side, I have been a little successful in reducing some of these calls. In the rare instance that I do get a live person calling me, I interupt them and say please hold on, there is someone at the door, I'll be right back. I then go watch TV, take a leak or what ever while they are on hold. After a few minutes I check the phone to see if they are still there. If they are, I then do it again. They DO NOT like it when you waste their time. They will NOT call back, guaranteed!!!
Please try it yourself and post your results.