Graphic corruption on 4.18 iMac

Hello everyone im asking about a very bad issue im having with my iMac.

A few days ago, only one level of my project started to have serious graphic corruption glitch
,the other levels are okay, only a single level is broke.
I only have this problem with the perspective and lit mode.!

cpu :3,8 GHz Intel Core i5
graphic card :Radeon Pro 580 8 GB

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I am also having this same issue. Does anyone have any ideas on what is causing the issue? It only happens with one project. This project is a real world production and as the lighting artist, I need to fix ASAP. I cannot light otherwise. This issue just happened (was working fine until two days ago).

I am the only dev on mac.

The above screenshot is an accurate visual representation of the issue when attempting to view in Lit, Lighting Only, Detailed Lighting, Reflections Only or through any cameras.
I’m using an i7 3.4, 16GB RAM, GeForce 680MX

Never had issue before, cannot reproduce - Project was okay and then it wasn’t.