Shadows issue on parallax occlusion landscape material

Here’s my problem, I have a directional light, a skylight and a lightmass importance volume added on my scene.
I added a landscape and multiple static objects on it.
My landscape receives shadows, all was good. Then I put a multiple layers material on my landscape, and in this material I added parallax occlusion mapping which works, except that it don’t receive shadows from any object on the landscape. Or the shadows are practically invisible, I don’t see correctly.
Maybe it’s just a wrong parameter in my scene,
Need help please :confused: