GPU-Scene Instance data overflow detected. reduce instance count to avoid rendering artifacts

[Griggaz]

Hello,

I have a level of 8x8km landscape and foliage in 1/7 of the map.
Nanite is enabled for the foliage, with optimised shaders, and textures up to 2k (Grass and bushes have 512px textures). I use the foliage tool with around 100k trees, 20m grass.

I get a warning about Instance data overflow and I’ve been trying to find a solution for a week with no result…
Does anyone have a solution for this?

Bellow I have screenshots from stats.

Thanks you
Ilias