I was getting the same on my cell.  When they called the house, the caller ID put a name with it was American Travel.  Took the call and they were confirming information on a card I filled out about two weeks earlier at an event for a vacation give-away.  They said mine was drawn and going into the final drawing, they just needed to confirm I had entered....so, we'll see.

we receive calls from this number many times. No message,

I didn't answer - they left no message