I am fairly new to using Archicad, and am having an issue with a mesh a made.
I created a mesh using a bounding rectangle from the line tool, and carved the contours by a combination of the magic wand function of the mesh tool and tracing lines by clicking on each point. Mostly, it is acting as expected, but there are some points on the edges of the mesh that will not move from the home level. I am not able to select the inner polygons to manually move these points down.
It could be that there are two points that are overlapping in xy-space but not z-space. Try to drag them down in the 3d-window and see if that makes them completely overlap and disappear.
I've had similar issues and it's been because there is a point on the "border line" of the mesh, and another point "inside" the mesh, connected to a ridge line, that occupy the same space in plan but not in 3d, so when you edit it in plan you are actually just editing one of them, and the other stays at the wrong level.
| AC 25 Int | Win10 | i7-7800X | 32 GB | GeForce RTX 2060 6GB |