when I answered, no one was there.

The same happened with me. No one was there when I answered and when I called back I was told its a "wrong number or code"

I just got that call and answered,
but there was some arabian dude. He said I
randomly entered into a free vacation sweepstakes.
I didn't believe it so I just hung up.
Before I hung up he asked if I owned a visa or master card etc....
Who the heck are theses people

they're calling my mom repeatedly and not saying anything

This was my second of 3 calls during the last 24 hours that I have not picked up. I don't like in the states right now so it's a bit frustrating.