they said nothing!!

I am on Do Not Call list.  The caller ID shows: MN HLTH Systems.  218-624-4574 is a Duluth MN number.
It actually shows a private number.  The woman calls every few days and wants to do a survey.  I have told her I am on the DNC list and she insists it is her right to call anyone for a survey.
I finally told her I was going to report her to the FCC.  She said she wold stop. We shall see.

I looked up the number 218-624-4574.  It is registered to a Susan V. Miller at 728 N 40th Ave W, Duluth MN 55807.  She is age 55-59.
Why does caller ID show MN HLTH Systems?  She has never tried to do a survey.  Just argue about her rights.  Appears to be a scam.  Could be trying to see if anyone is home?
DO NOT ANSWER THIS CALL.

This number is being "Spoofed" by  Delta Outsource Group, a collection agency located in O'Fallon, MO.  They will try and gather enough information to create an account.  Many bank accounts have been drained by this establishment and many "Spoofed" phone numbers have been fraudulently used to aquire information.

Received a call from this number, they did not leave a message.  The number is registered to Susan Miller on 40th Ave West in Duluth.  I don't know this person.  Does anyone know what she does for a living?