Android optimisations?

you were right, i had just clicked it on from world settings, when i enable “warn about…” from rendering, it immediately warned me that no precomputed visibility. The scene i’m using hadn’t used precomputed visibility volumes so i added couple of them to cover whole scene. But i don’t know if i’m doing right because i haven’t used it before.

In the editor, It still says “no precomputed visibility” even after i added volumes in the scene.Is it okay or is there another way to add them in the scene ?