Whitepages, phone reverse search says: Scam or Fraud.  Flagged as Extortion, (870) 283-2336  AT&T Mobile.  Cave City, AR.  & this is the VM it left: "The reason of this call is to inform you that IRS is filing lawsuit against you to get more information about this case file. Please call immediately on our department number 870-283-2336. I repeat 870-283-2336. Thank you." / I've heard the IRS only writes to about these matters.  Such a PiTA!