UE5 rendering bug: Severe rendering issues (lit looks worse than unlit)

I have been working on my game for quiet a while now, every thing was fine until i booted up my game and I find that the rendering is completely messed up:

and note that this is LIT.
This is the infamous rural Australia level by the way.

what happened in the session before it:
experimented with culling, here’s what I did:
I setup a culling volume then, set the culling distance to around 10000 but the size was maxed out (more than 9 billion)

In the image the culling volume was removed, however the engine was still culling although there wasn’t a culling volume.

what I tried:

  • Build every thing.
  • setup culling volume with normal values.
  • contacted ChatGP, but it didn't know what to do.
  • I fired up another level but the problems are still there
  • I fired up another project and the issues are gone, so it's a project specific issue

notes:
I can see through thing, and from surface level it looks worse than what the screenshot is displaying

Any help?

<3