I have had VoIP for years that have filters on it, also now have NoMoRobo and after a while they stop calling or I get the "One Ring" intercept. I moved my Mother over to it after having to clear the telco and phone blocking alternately every month of scam calls, and once I got them all use to just letting it ring and if they don't know the number letting it go to VM, the call rate has dropped dynamically. And it all started when Dad had to answer all calls and talk to every one. That put them on all kinds of lists. But with a little time and resources, it'll smooth out. I can look at the call logs for both accounts and there are relatively no SPAM calls anymore.