What can I do about a debt collectors threatening?

This person who identified himself as a detective from a 913 area code told me I had a debt from 08 that I can’t remember ever having. They say they are signing an affidavit for a warrant for my arrest. I paid half of the debt which was 300 backs scared I was going to jail. They were supposed to send something verifying I paid and if I didn’t I was going to jail, I’m in AZ. This person has told me that I will go to jail for 385 bucks and not see my child for a long time, is this legit, they aren’t even in my state.