if i had a debt and the last payment was made in 2002 while i lived in the state of texas is that debt collectible?

I got divorced in 2003 and the judge had ordered my ex to pay this debt (approx $1100.00) but he never did, there hasn’t been a payment made since 2002. Now I am getting harassing phone calls from a collection agency telling me it is my moral responsibility to pay the debt. I was under the impression that Texas had a statute of limitation of either 5 or 7 years and after that point they couldn’t collect on it. Am I wrong in my thinking? What do I need to do? Every time they call me they begin to yell at me when I tell them that the debt is uncollectible and I just need to make sure I am not provoking them to pursue further collection efforts. Please help.