he keep calling me and I totally have no idea。。。

Same, I keep getting calls from this phone number and have no idea who it is. I keep getting a half second blank voicemail.

Scumbags keep ringing once then hang up.  My guess is that ur number is given to a third party call center by a collectiom agency whom is unsuccessful for collecting a debt from u and their sole purpose to harrass u

This is a computer called collection call. In my case it is most likely Portfolio Recovery, but the service could be from any other spammer, if they are a hired call center. I just call them back about 15 times, and say nothing. They also called back one time and tried to hurt my hearing with their dial tone, but I use my speaker on my cell phone, so it did not work for them. If you continue to call them back numerous times each time they call, they may take you off of their list. They also announce that it is a recorded call, which is typical of a collection agency call.

Not a smart idea, engaging the scammers. At the very least you'll get more calls. Or they could "swat" (look up swatting) you. They also could start using your number as a spoofed number when they scam call other people. Wouldn't that be fun? Keep in mind that many of them are most likely overseas, they feel they have nothing to loose. Can you say the same thing? Just do not answer unknown calls and do not call them back.