These people are scammers, and they  try to get your info.
When you answer the call they try to intimidate you with, Oh I'm Inspector so and so with your file case #.
Do not get them any information.
It could be a company called fidelity collections,and it is very hard to track their #.
I have the FTC try to work right now, to stop this company from harassing the public.

Received two calls back-to-back from this number.  They left no message; which is a strong indicator that this is not a call you want to accept.  Looked it up here and opted not to return the call.  Saved the number in my Contacts as 'Fidelity Scam'.  Planning to get a new phone and new unlisted phone number soon anyway.  I figure it took them 10 years to find my number in the first place.  Let's see if they're still around 10 years from now . . .

Received call from "Investigator" Gate or Gail (garbled her name).  I asked her what government agency is she with.  She said that it is a private firm.  When I asked more questions then she put me on musical hold.  I hung up.

They keep calling my daughter saying I have a case and tell here it is life and death that they reach me. I have no idea how they got her number, as I never give it out. When she told them to stop calling or she would call her lawyer, the "investigator"  laughed and told her he would call more often, and has since called her three or more times per day. They call from this number, but leave an 800 number for call back. They are a menace.

THIS NUMBER IS FROM A COMPANY CALLED COLLINS AND STERN AND THEY ALL CALL THEMSELVES INVESTIGATORS LOL I TRIED TO LOOK THE COMPANY NAME UP BUT IT DOES NOT EXIST  SMH