He said his name was Jeffery Smith and when I asked him what his call was regarding was regarding for my boss, he wouldn't tell me so I hung up.

These a-holes have been calling my cell since early March, 2016, sometimes more than once per day.  Thanks for stating his "name".  I've never been able to get that.  Jeffrey Smith, yeah, Smith, right.    My research has shown so far that these people are running a scam as "Who's Who", pretending to be the real marketing/branding company.  They say they want to ship me something and want me to verify my address and give them a credit card authorization.  I told them more than once to quit calling me but that doesn't work and unfortunately I cannot block their number at the moment (still trying to do so).  Of course, I don't bother to answer and don't let the calls go to voice mail.  They still keep trying and I just got another call just moments ago.