Blend nor Fillet Edge Works

I can blend and fillet most of the edge, but not all of them. Why? I have mergeallcoplanarfaces which helped some of the edges.
edges.pdf (1.7 MB)

Hi Bridget - it’s hard to say without the Rhino file - can you post that here, or if it’s confidential, send to, to my attention, with a link back to this topic in your comments?