They keep calling my work number.

me too and who are they cant call them back ?

Received a call from this number at 1905 hrs but there was no one on the line.

Left a message that sounded as if it was from a cell phone with bad reception, and subsequently impossible to decipher.  Dialed the number from my call display, and received automated message which stated, "we're sorry, your call can not be completed as dialed..." .