Federal tax lien problem?

It's possible they probably will want to investigate first to see who stole your identity at 5 yrs old. This usually happens when family members use childrens info to get credit or it is stolen from financial or medical records. Minor are targeted for identity theft sometimes because it takes longer to find out if they have something on their credit. An example would be in your case. Actually what you will want to do is dispute it to the credit bureau.