Randon points no longer apply to surface

I am on my first Civil 3D project and getting very frustrated.

I have created a point group of catchbasins tops to apply to my surface. Every once in a while, a point within that point group will no longer be applied to the surface.

Anyone have any idea why this might happen?

First verify that the point(s) is still a member of the group.
Second verify that within the Surface properties BUILD tab that these is not a setting in there causing the point(s) to be ommited.
Something like a do not include points lees than, or greater than setting.
Also verify that those points are not being excuded due to being a 'duplicate' point.
Lastly check the edits collection within the surface definition to ensure someone hasn't decided they should delete that point from the surface definition.
If none of the above reveal anything, feel free to send me your file for a more complete review.