Permanent hair part in back of head?

I have a permanent hair part in the middle, and I don't mind. The thing is - I don't like how the part has started to keep going to the back of my head. If you look at me from behind, you can see my part continuing. How embarrassing! How do I get the top, back of my hair to just lay nicely "without" parting? No matter what I seem to do, it just keeps separating.