Huskhawk Group, LLC Called to say that I owed money from 6 years ago for a $400 loan that I dont recall Internet

I had the Huskhawk Group call me to say that I was going to be served on a civil action if I did not resolve my "past due check loan from 2010".  THis is now 6 years later.  The company had addresses that I lived and and even the last few account numbers of my previous bank account.  However when I asked them to send me the correspondance of emails they refused to and said that they dont do that.  I asked them to send me an agreement so I could look over it before I signed it and he refused to send it because I had to stay on the phone with him and sign it.  I had to give him an answer immediately without being allowed to look at any paperwork or they would have me served at work with papers to move the matter forward at court.  From there he said that they would seek the amout of the loan ($400) and attorneys fees and court costs.  It would be around $1900 where they would then have a judgement placed on me and hold all my federal tax return and garnish wages, etc.  He also said that he has someone on site right now to serve me paperwork.   This company is not legit.  And why after 6 years?  Im not sure but there must be some type of statute of limitations.  The number they called from was 1-855-206-9697.