This is a debt-collection phone scam. I've been hounded by these jerks, too. I actually called them back (called "URG") to figure out who they are and why they're calling me. They refused to disclose any information about what their company does until I gave them my phone number (I had blocked my phone number from showing up when I called them). Check out this link from the Better Business Bureau on this type of debt-collection phone scams. http://www.bbb.org/blog/2013/03/beware-debt-collection-phone-scams/
Caller: "URG"