Do what I did. Get a phone with a blocking function. I bought a Panasonic that blocks up to 250 numbers. It runs about $50. It has a lot of other great features. You can't stop all spam but you can stop the ones that keep calling back. Just takes a few clicks to block. You can also set it to block unidentified numbers.
Reporting calls does not help. The numbers are fake and they keep changing. The FBI offered a reward for information to catch the fraudsters with the "Rachael from cardholders service". It took years to bust 5 operations and I'm still getting calls claiming they can lower my credit card interest. Most of them now start out "this is your final notice".
Yes, and now I've started getting calls from within my own exchange that are successfully fooling the "no more robocall" service! And they come complete with a valid "name" entry on the caller ID!