Thieves are taking over the phone lines call and call and never leave a message. If a phone call is important they leave a message if no one answers the call.
Could be a wrong number.
My cousin called me once from Montana and all that appeared in my online logs for my landline was the number and "Wireless Caller"
He had never called me before with his cell phone.
I have read this is typical of a lot of cell phone calls.
They keep calling at different times, no message, nothing. Not answering it cause I don't know the number, must not be important or they would leave a message