Payday loan harrassment

I was living in PA and had a payday loan via the internet. Had to leave PA to escape an abusive husband so loan was defaulted. Now, 6 years later I have some company called Communication One Inc (this is what comes up when I do a reverse search, calling saying they are taking legal action, etc, etc. Their number is 518-621-58**. Ever heard of them? Oh, they also claim to be from a law office, no name, and from the National Check Registry. They are located in New York. I now live in AZ. At the time of the loan I think they asked for a check. So - is this fraud? I think it's passed the statute of limitations. If they do not practice barbaric recovery tactics I am willing to work with them - but - if they're are going to make threats the can get lost. What's the best way to deal with them - I've asked, via voice mail, for them to send me in writing the information. I don't have a clear name or address for them.