I have a seat phone so if I get a call from a number I don't recognize I Google it to find out its history. Then if it's no one I know I just add it to my blocked caller list and I never hear from them again.
386-361-4000 received call on my tmobile cell phone to get a free security system if I advertise a sign on my front lawn all year. I clicked yes to talk to a human and asked where they got my cell phone number. They said their corporation buys cell phone numbers from Tmobile. Tmobile sells all cell phone info to corporations to increase profits. They said if you don't want to get called, just cancel your cell phone service. They said they need to make a living too, and if you can afford a cell phone, then you can afford a free security system just advertising on your front lawn or if in a condo, a sign in your front window facing the street or sidewalk.