Caller ID said 'NOT IN USE'. I almost laughed. Someone chose that one. So, since it is not in use, I picked up, but said nothing, and was responded to in the same way. After about 20 seconds I just hung up.
Why bother being on the No Call List when these type of calls keep coming....repeatedly! I see the number & deleted the call & that's more time than I should have to give them.
I no longer answer the phone for numbers I don't recognize. When you do, and it is from a marketer or scam, you let them know that they have a valid phone number. This is especially so if you press any key even if you believe that it will take your number off their list. My calls have significantly reduced since I stopped answering. They sell that information. They make sure to sell it if you are not nice to them.
I also place the number on my ZZZ list. Save the number and name it ZZZ. That ZZZ will show up on your screen and then you definitely know to not answer it.