judgments

While incarcerated six years ago, my wife secured the services of a law firm to handle a child support matter. I signed a document giving her the authority to do so, (power of attorney). The law firm has perused a judgment against me. I called the attorneys of the collection agency and told them I was responsible for the bill and made arrangements for monthly payments. My wife just received a notice of judgment for the same bill. Can they bring a judgment against my wife when I have already made arraignments with the collection attorneys? What do I do? Thank you, Peter Del Rio Niagara Falls, NY