They do not leave a message because a computer dialed your phone. If you answer and all the scammers are on other calls, there is no one there. If they have an open line, a scammer will come on to talk to you. HANG UP....DO NOT TALK TO THESE IDIOTS...YOU TALK, THEY SELL YOUR NUMBER TO ANOTHER SCAMMER BECAUSE A LIVE PERSON ANSWERED. IF YOU LISTEN TO THEIR LIES AND GIVE THEM MONEY, VERY LITTLE OR NONE OF THAT MONEY WILL GO TO CANCER RESEARCH. If you want to give a donation, look up American Cancer Society and ask them where to send your donation.