You can download an SIT.wav from Google. Record this tone at the start of your voice mail message. It generates the tone that tells the computer that "this number is out of service." (or unavailable) When their computer hears this, it deletes your number from being called again. I had my son do this for me a couple of weeks ago, and it is amazing! You do get a call from a robocaller, but they don't call again. How peaceful. Good luck.
Sunday Morning scammer! This is a fake charity for fallen police officers. The same crooked family's setting up these fake charities. They even have an Ivy league college course how to set up a fake charity. The deal is usually 90% for the charity owner and 10% for the named beneficiaries. They even cheat on the percentage until it is 100%/0 % because the current government gets donations from them to look the other way. If your phone number is listed in the phone book, then you will be pestered by these vultures. Better to bribe the crooked phone company to keep your number out of the book. Either way you pay.