Hi Rachel, can you please post the 3DM model file in it that contains the curve you show in your screenshot there?

That would make it a lot easier to answer your question because the problem is potentially something specific to your particular curves, like especially if one of the curves is closed and the other one is not closed that could be your problem. It's difficult to know such details just looking at a screenshot, that's why it helps to post the 3DM model file as well.

In Loft when you are lofting between closed curves in the final stage of the loft command where it says "Loft options", there will be some marker points that appear on the curves that look like this:



You can click down and drag those marker points to control how the curves connect to one another, that's generally how you can control the twisting between closed profiles.

If you do not see those markers it probably means one of your curves is not actually a closed curve, it has some gap in it making it an open curve. You can see if this is the case by selecting each curve and then looking at the object type indicator in the properties panel in the upper-right corner of the window. The object type will read as "Closed crv" if the selected object is a closed curve, or just plain "Curve" if it is an open curve. When you have a mix of open and closed curves in a loft you will not be able to adjust the seam location as you can with all closed curves.

The other thing that can happen with lofts that can be complicated is if your loft profiles are made up of many different sub-segments with each profile having a different number of segments in it and also having sharp corners within the profile. In some situations with complex segmentation like that, the lofter will have some difficulty doing a good job of matching segments together and you can get things like things connecting halfway through some individual segment rather than matching how you need. When that happens usually the cure is to do the loft in smaller chunks with only doing one section at a time between sharp corners rather than trying to do it all in one single loft between large complex segmented curves. When you do the loft in smaller sections you then more manually control how segmented pieces will match to each other.

Hope this helps, and if you need further tips with a specific model please post the model since that helps a lot to diagnose the particular issue at hand.

- Michael