I called them back and got a standard message of "to be removed from our call list please leave your name and number to be removed from our call list." Then an operator comes on and says the message box is full. Might be someone trying to get names and numbers to sell to information companies.
Last week this number called me like 4 times in an hour.
The last call I picked up the phone and yelled
" Hey I'm busy banging my wife, can you PLEASE call back later"
Multiple calls from this number, usually in the evening. They leave silent voicemail. When I call the number, I go direct to their voicemail, asking me to leave my name and number to be removed. I've left my number but they continue to call. When I answered, there was silence, then they hang up.
They called back. A reverse lookup shows this is a T-Mobile number. From the background noise, it sounds like a call center. It's some car warranty company. They have illegally called me on weekends.