Legal Question in Credit and Debt Law in Virginia

They may have bought the debt from the original creditor, or from someone else. They almost certainly cannot prove the debt without your own testimony, but if you owed the original creditor they may be able to make you testify (which you are required to do truthfully). Of course, the debt may be time-barred, not owed, or subject to other defenses. But mere charge off is not a defense - it's just an accounting entry. You would still owe it. You should see a lawyer about defending the case.