Hi billis, the gap in your sweep at that point is because your path curve has a sharp cusp in it at that spot and is not smooth there.

If you turn on control points for the path and zoom in to this area:



You can see that the last points are not arranged to be tangent, they meet at an angle, so those 2 segments of the curve also meet at an angle and are not smooth to one another:



To fix it, I would suggest selecting those 3 points and then run Transform / Align to line them up vertically. That will make that area smooth and then after that it will generate a sweep that is also smooth there.

- Michael