unknown number calling

Called by cell phone twice.  First time missed called call - now message left.  Second time I picked up but got dead air.  I hung up after 30 seconds of wasting my time saying "hello...?"

Annoying.

This number is the Company Corporation.  A business that people use to incorporate and use as registered agents.  Usually a call regarding an account.

Rec'd  mult calls -- no msg - nothing ?????????????