Gap with Loft

I have this curved angled surface I’m trying to make and when I do loft, it makes this gap. I tried the other loft options but it still has the gap. How can I extrude the base curve so that it meets the top curve?

I guess the problem is that you rebuild your input curves with 10 control points, which changes the curve morphology (for lack of a better term). You shouldn’t refit or rebuild, when you rely on the loft to fit precisely.
Rebuilding can have a smoothing, or rather simplifying effect on curves! When you for instance have a curve with 150 control points and you downsample it to only 10, Rhino needs to compute or interpolate larger curve segments between fewer control points that thus have less resolution.

thank you!

You’re welcome.