Ideas
I encountered this issue at the end of May when I was building my 4-unit rental property. I only now realize that this was/is a bug.
I thought that it would be better to rotate it 180 degrees, which I then did. I saved it in my library and when I placed it again, I noticed that there was furniture, decorative items, and building components (windows, doors, etc.) flying around in and around the lot. I tried to counteract this by deleting them several times and saving and loading again. I didn't really succeed. Even leveling the terrain or the entire property didn't help. So I took an empty plot of the same size from another location on the map or from another save file, saved it in the library, and then placed it on the property in question, which was causing these problems. After that, I placed my building from my library again and was able to continue building without any problems. The floating models and components did not reappear.
Library
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