Wow!!... This was a shot in the dark but seems to have solved the problem. Select Merge tangent faces on your sweep.
The Lpattern will fail but all you have to do is edit that (don't need to do anything else). Just click on the green check mark. Edit:.. Actually don't need to edit. just do a Ctrl+Q and that will fix everything.
It solves very quickly.
Wow!!... This was a shot in the dark but seems to have solved the problem. Select Merge tangent faces on your sweep.
The Lpattern will fail but all you have to do is edit that (don't need to do anything else). Just click on the green check mark. Edit:.. Actually don't need to edit. just do a Ctrl+Q and that will fix everything.
It solves very quickly.