The National Do Not Call Registry. You can add home or cell #s to the registry. It's intended to keep people from making sales calls to your number. Scammers ignore it and call anyone that they want. The number of someone who calls, in violation, can be reported to the fed government. It's not designed to stop people you have done business with, have had a slales interaction (ie car dealership you looked at car at, or bill collectors from calling.
I just received this call on my cell phone. Recorded message saying my student loan has been flagged for loan forgiveness. My student loans were paid off at least 10 years ago.