Landscape Spline help please

I am using the landscape spline (First time) and I am trying to create a road with sidewalks. The road works just fine but when I try to add sidewalks to it the road comes out like this:

I added the sidewalk to the spline under the road as you can see in the picture, I did that so the sidewalk would move with the road when I moved/created it but it seems to have cut the road for some reason. What am I doing wrong?