As of today (4/18/19 - and the day isn't over yet) we've had 78 calls from this number since 11/8/18. That's just over five months. If we're in the office the calls are disconnected by our software because we block anything that doesn't have least a name OR a number. My phone's CID always says Unknown Name, Blocked Number, and the software we use shows it as Private, Out of Area - so the calls ring one time and are disconnected. On Comcast, our phone service provider, these calls show as Anonymous, 999-999-9999.
I have blocked the number on Comcast. This will prevent the calls from even ringing through to our business, but it doesn't block the 999-999-9999 (or 100-000-0000 for that matter), leading me to think it's spoofed.
They NEVER leave a message. They spoof or withhold their real identity and their real phone number. That proves they are frauds/scammers. Legitimate callers provide the information. Outright harassment is what this is.