Oculus headset detached while oculus attached with the pc

I am working on the Oculus project, The player character for my simulation in Unity.  in which I have firstperson controller, I have created game object of player in which I put FPCamera as a child and character's body.
Issue: When I attach my oculus camera it detached from the body and with the Oculus headset movement, FPcamera act as a separate view from the body. the body does not rotate and remain static even though FPcamera is moving according to the headset. However it works fine if I disable oculus and move the character with the mouse, I can see my body and move left right everything with all animations.
I have the following link for the oculus controllers  integrations in my project
https://assetstore.unity.com/packages/tools/integration/oculus-integration-82022 (Oculus integration)
here is a link which I have to achieve for my project, my FirstPerson should be like this in Oculus. you can see that the movement is with accuracy according to its headset movements
https://www.youtube.com/watch?v=7GpxsI-Tag
Note: I am using Unity 2017, there is no crash report in the project