Has your cell phone been ringing people on its own, and otherwise messing with you lately?

Recently I was in the car and my cell phone rang. I answered, said ‘hello’, and there was nothing. “Hello” again, and a woman says “HELLO! Did someone just call me from this number?” I answered “no, they did not” and she hung up. I had a couple of other unusual calls that day.

Today my phone rang and I didn’t know the number. I called it back, and it was a friend of mine, but she said, “I didn’t call you. I’m driving the car and my phone has been laying on the seat beside me.”

I’ve been getting an unusual number of solicitation calls.
Is this something with the solicitors hijacking people’s phones to make calls?
Anyone else experiencing this kind of thing lately?