I couldn't solve the issue no matter what I tried.

There were no problems before, but something happened to the program. Strange light ripples and shadows started appearing in the building. Even if I open a new file, the attached visuals don’t change. I uninstalled and reinstalled the program, but the result is the same. When I place the furniture outside, it looks normal, but when I place it inside, it appears as shown in “image 4.”