Someone from this number keps calling me and when I answer after 2 rings they hang up or don't speak.  Day or night, doesn't matter.

got a call last night at 19:26, did not answer,  no msg. left.

I got a call from this number at 7:20 this evening. I didn't answer because I didn't recognize the number. After a few rings, they hung up. Less than 10 minutes later, the same number came up on my caller ID again so I answered. It was a pre-recorded message and I hung up.