You should consult with a general civil litigation attorney after you read this answer. It seems that you were sub-served with the summons and complaint at your grandparents house. There is a judgment entered against you probably for a sum of money.You need to set aside the default and default judgment on the grounds that you were not personally served with the summons and complaint and that the sub-service was improper because you did not live at your grandparents' home where the summons and complaint were served upon you through them.You need to start attempts to set aside the default and default judgment right away. The longer you wait, the harder it will be.You could contact the county bar association to see if it has a program where attorneys volunteer time to help people like you.