Per willshak:
https://www.donotcall.gov/

Does it not work for you?
It's worked for me since I registered when it first came out 9 years ago.
I have not gotten any telemarketing calls in all that time.

Count your blessings. It used to work for me too. No more.

And I have a stack of lame letters from the Penna Atty General's office
in response to complaints lodged at the Penna DNC list website to the
effect of "The world has moved on. These guys are now offshore hiding
behind VOIP, sometimes with multiple hops and there's nothing we can
do."

I would disagree with the last thought, but it seems clear that the DNC
lists are on their way to being history.
--
Pete Cresswell