Your cell phone call and nobody there?
These guys looking to sell live numers.
http://www.cell-phone-list.net/index-2.html
Why Phone Fraud Starts With A Silent Call
https://www.npr.org/sections/alltechconsidered/2015/08/24/434313813/why-phone-fraud-starts-with-a-silent-call
That initial call you get, with silence on the other end, “[is] essentially the first of the reconnaissance calls that these fraudsters do,They’re trying to see: Are they getting a human on the other end? You even cough and it knows you’re there.”
Company researchers estimate 1 in every 2,200 calls is a fraud attempt...