same here. my experience (infortunately that is a lot), when the number is "not a working number" or "no longer in service" or something like tha, it is a scam and the number has been spoofed (it is a bogus number).
now I blocked it.
Missed call. Left no message. No valid caller ID name, so my phone service provider (I think) apparently filled in the location of the caller as New York, NY (which means Manhattan), even though area code 718 is an outer borough area code. I don't know if that means that the caller was using a cellphone while in Manhattan. Or maybe the caller just spoofed the location.