I need to set X rotation of object same as X rotation of VR controller

I've got a object which has the x rotation same as controller of vr.

Code (CSharp):

1. transform.rotation = Quaternion.Euler(controller.transform.rotation.eulerAngles.x, 0, 0);

But I need to rotate it 90 degrees that the object will be vertically not horizontally.

Code (CSharp):

1. transform.rotation = Quaternion.Euler(controller.transform.rotation.eulerAngles.x + 90, 0, 0);

But this doesn't work properly, because you can rotate the object in only one direction.

If you rotate controller right -> object rotate right & if you rotate controller left -> object rotate right.
If you want to rotate object left you have to rotate controller upside down.

I also tried set the object as child of controller but on play the object disappear.