OnCollisionExit is not working right...

I am trying to cause that when the player step on piece of road it will have a gravity and fall down.
However when I start the game the piece of road the the player stands on fall down before the player moved to the next piece.

*The gravity and the kinematic are off.

public GameObject Player;
private Rigidbody gameObjectsRigidBody;

private void OnCollisionExit(Collision collision)
{

    if (collision.gameObject.tag == "ground")
    {
        collision.gameObject.GetComponent<Rigidbody>().useGravity = true;

    }
}

When i start the game:
172190-capture.png

It sounds like you should either make it so the first piece of road is static without a falling function or you should put a timer on it to start falling X seconds after the game starts:

bool enableFall = false;

void Start()
{
    StartCoroutine(Timer());
}
IEnumerator Timer()
{
    yield return new WaitForSeconds(1.5f);
    enableFall = true; //allow road to fall when collision happens
}