Deleting Point on Polysurface after split / cut

Hey gang,

does anyone know how to delete this control point on a polysurface? "Remove control point " isnt working for me.

The file is also weirdly large for a single layer. not sure whats up with that…ive already purged and save small.

Kindest,
Liam
poly.3dm (18.8 MB)
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