FTC The Federal Trade Commission goes After VOIP Providers

Many of the robocalls you get come from International Call Centers 
using VOIP providers to make the calls. They use whatever Caller ID they program in.
So it is nearly impossible to track them down.

It takes a huge financial commitment to track the offenders down and the average consumer just has to take the harassment. 

Finally, the FTC is attempting to go after the providers of the services.
Let’s see:

https://www.ftc.gov/news-events/news/press-releases/2023/04/ftc-ramps-fight-close-door-illegal-robocalls-originating-overseas-scammers-imposters