Rhino File suddenly went 188GB after saving it!

It’s just a building with some terrain mesh in it.
After making “make 2d” I tried to export the result as dwg but it was stuck exporting after several minutes. I decided to re-open Rhino and that’s when I saw 188GB file size which is EXTREMELY HIGH and Nonesense.

Problem is now I can’t open the file anymore because it’s too heavy. (I have 128 GB ram and in Task Manager is using 100%).

What can I do?

check your trash for an autosave that wrote before you did the make 2d.