Help with twisting variable pipes

Hello, I have been using the pipe variable component in grasshopper on a series of closed curves coming from the same continuous surface, using the command in rhino isocurve.

Despite the control points and tangent points seem coherent for each curve, I am having undesired results on some of them, it seems that they are just self intersecting/twisting compromising the continuity. Please see screenshot to understand the issue.

Does anybody know how to sort these out? I’ve been struggling for a while