How do I correct this?

And now I am paying for it.  Sometimes I get so into something that I am drawing, that I can't see the forest for the trees.  A couple of days ago, I posted a blog about using grisaille as an underpainting for colored pencil.  I was just at my Tuesday am art group and had one of my colleagues point out a flaw in the persepective on the building.  Now I have to correct it and I have already sarted to put color to it.  Here is the beginnings of adding the color.  Tell me if you can see the flaw.  Tomorrow I show how I will try to correct the persepective...