Amateur with Blender here, using 2.8, having an issue with the Subdivision surface modifier. I have a very simple shape here and I'm trying to extrude while using the modifier, I have this one part of the mesh that sticks to the edges of the model.
I've tried everything I could think even, I've even deleted all the vertices in that area and rebuilt it from scratch and that darn thing just reappears. If I delete all the edges and then just fill in the new face, it'll just move to the next edge down. I definitely don't have any overlapping points.