As you can see in the screen shot, my model is aligned in the perspective view, the right view, and the frontview, but not the top view.
What did I do to cause this, and how can I fix it?
You’ve set a CPlane in the Top viewport with an origin moved away from the World Origin. To get back to the default set the CPlane for the Top viewport to World Top:
HTH
Jeremy
Thanks Jeremy!
It fixed it!