What kinda of laywer do I need?

My dad is living in the house I own. Three years ago he took out a 250,000 dollor lien on it. I never signed any paperwork allowing him to do so. I contacted the laywer who let the lien go through, and he said i need to sue my father. He won't remove the lien. How do I get it taken off of my house? The title to the house is in my name I do understand how they ever let him get a lien on it in the first place.