I received a phone call from this number as well and they didn't leave a message. I called the number back after reading all your posts and the same thing happened-the phone message said "this number is not in use"
FILE A COMPLAINT WITH THE NATIONAL DO NOT CALL REGISTRY! BUILD A CASE AGAINST THESE GUYS!
LINK TO FILE A COMPLAINT WITH THE NATIONAL DO NOT CALL REGISTRY (RUN BY OUR GOVERNMENT):
https://complaints.donotcall.gov/complaint/complaintcheck.aspx