Landscape material discoloration issue

Hello all. Have not been able to solve this issue that appeared some time ago. As i was working on a diffrent part of the map i did not catch when it happened and am stumped at this point. Any suggestions why several sections are darker or discolored?

Rwally, they just look like different materials are applied.
Isolate them, check, and if that isnt the case screenshot a bit closer.

Hello, It dose not seem to matter which material i choose. also it appears to follow a mirror image of landscape paint on another portion of the map

Those are definitely different materials or material instances with different settings - you can see that by the repetitions of the texture on the mudd/grass.

I’m guessing the difference in color/shading is also due to some other different settings or setup - like the roughness map or similar.

i have the same with 2 different materials

how to fix it?