They call me 2-3 times a day EVERYDAY. Usually I do not answer unknown numbers, but I'm sick of them constantly calling. Hold music for 15 minutes then it just disconnected
This number called our private business line again today and again left no message so I called it back and the message says that the number has been changed or disconnected. I wonder how they're able to get that message from a line that just called us 30 seconds before? Hmmm
Google Voice can do it - they just program in your number to be blocked.
https://support.google.com/voice/answer/115089?hl=en
Block unwanted calls, abuse, and spam
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Block Caller: The caller will hear a "Number not in service" message when calling your Google number. None of your phones will ring. Blocked calls won't show in your call history as missed calls.