I just got the same call from them at my place of business,  The guy who left me a voice mail his name is William Brown.  He said a Mr Allen Smith has signed off on my case and I have no idea who this is and what type of scam they are running.  If its a real business they would not block there number.  They said my case number is 143197-CA124.  This is a scam.  Don't let them scare you.  Laugh at them and hang up.