Depending on the type of cell phone you have, you may be able to block calls from a particular number. My smartphone has an app called Mr. Number Block, which can be programmed to disconnect or send to voice mail calls from whatever number is programmed into the app. There are other apps which work the same way. You can also block calls from numbers that show up on Caller ID as “Private” or “Unknown.” The app works very well.
Your case isn’t even the same as theirs. The Federal case they pursued involved debt collection practices, which are covered by a law that probably wouldn’t apply in your case. The other Federal statute referenced in this case (a Federal telecommunications law) might apply, though.