Questions about Cube Map Reflections

I have a simple question.
Reflections from cube maps appear to be coming through the object.

One object is outside, the other in a blackbox.

Cubemap is reflected on object located in closed blackbox.
I don’t want reflections on objects in closed space.
I don’t know how to make it possible.
And i don’t know why the cubemap is reflected.
This is my test project.

It may be a silly question, but i wait for an answer.

It’s a material property, you have to untick ‘Use skybox’ on the material

In this case, you would need two materials, one for when it is in an enclosed space, and one when it’s not.

If you want true reflections, you would need to create your own skybox and use cameras to render to textures and be applied to the material as a cubemap.