Drape Tool Crash


I add the roads on the terrain model. But when I add the buildings and landscaping, it becomes like in the picture. I’m about to go crazy now. Please help me.

From the photo you can see that some faces have disappeared and some lines have not been created, but that doesn’t mean that ‘Drape Tool Crash’.
Use the Line tool to recreate those missing faces and lines.

In fact, after applying the ‘‘drape’’ command, the surface on the terrain model disappears.

The surface that disappeared was created by one or more faces and lines, that’s what I wrote.
Use the Line tool to recreate those missing faces and lines.