This scumbag calls repeatedly leaving NO message and hanging up when you do answer. This can't be any legitimate caller representing any legitimate business or legitimate concern. These people are gutless, mindless scum who will be hunted down and stopped.

They are Level III Communications.  They lease 'local to your (area code)' numbers to folks who do not want you to know who is really calling. For example, a Bill collector whose other numbers you may have blocked, but the leased line is not. A side-door attempt to get you to pick up.  Creeps.

CID showed MANITOWOC WI - the number is remarkably close to a series of other known to be scumbag numbers that we get with some regularity and had the telltale clickover from an autodialer to a call center giving me ample warning to not speak by the time a clueless woman started saying hello repeatedly for twenty-five seconds.  Another one added to the list.

CID showed number 119204822449-autodial changed over to a recording for the first time, male with southern accent:  "Hello.  This is Technical Circulation Assistan" and the recording abruptly cut-off of as the call disconnected itself.  Scum, scum, scum, scum, scum.