I keep getting these calls from the same number and no message...getting to be a pain in the zzz.

I've received multiple calls from this number but a message is never left.

Have been called twice by this number--once on 7/17/13 and today, 7/19/13,  Caller ID on the first call indicated Reidsville, NC.  Caller on ID display today indicates "Out of Area".  Answering machine picked up both times but no message was left.