It probably works, but why pay them to get you signed up?

There is a federal no-call list that you can call to sign up, or
maybe do it online for free. Indiana has a state no-call list that
was proposed by our Attorney General two years ago & voted
into law. The sign up was free & I'll be eternally grateful to him
& the state legislature for the rest of my life.

Honestly, I was getting 10 to 15 calls everyday. They even had the nerve to leave their sales pitch on my voice mail. It was very annoying. But not anymore, the silence is wonderful.