Green points can be swept, red points can not be swept. As long as all supported linear objects such as line, polyline, spline, arc, spiral butt, the result is successful. Although one of the red points above seems to be closed, actually the two lines at the corner do not butt. In some cases you may have to show the same area from different places. If it is not swept but everything seems to be true, probably there are lines very close but not touching each other.