I have a phone bill past due and sent to collections. The debt is so old that the company, which is Sprint, no longer handles land line phone service and hasn't for quite some time. They can't tell me how to pay the bill with them directly. I've already paid $50.00 to the collection agency for the debt before being told to have the agency validate the debt first. I need to know what to do if the agency doesn't or is unable to validate the debt.