That's very strange.

I won't answer my phone unless it's from a person in my "contacts."

If just a phone number pops up with no name while I'm getting a call, I refuse to answer.

Same here. Normally only answer numbers already in my contacts. I have an extremely small circle. 4 Siblings, their wives/husbands, 5 co-workers, My elderly Mother. That's it. When the calls first started, I did answer. The numbers were from all over the US, and when I answered I would get a computerized female voice that simply said, "Hello"... nothing else. Whether I responded or not, then a pause, then it would hang up. In the last month, the numbers are all from my home state, but with no "Hello", just silence. In the last 3 weeks, I just hang up as it's ringing. The calls are fewer during the day as long as I don't move locations. If I do go somewhere, I get a call. I know what I sound like as I type this, but all I can do is report what I experience. It is unsettling, but I put it out of my mind because I think the purpose is to unsettle me. I lead an extremely simple life. Work, home, grocery store. No known enemies, no relationship drama. It's just flat weird.