player isnt moving based on rotation unity code example

Example 1: hwo to prevent rotation after hitting an object in unity

private void OnCollisionEnter(Collision collision)
{
	GetComponent<RigidBody>().freezeRotation = true;
}

Example 2: look rotation only on y axis in unity

var dir = PlayerMovement.playerTransform.position - transform.position;
        Quaternion LookAtRotation = Quaternion.LookRotation(dir);

        Quaternion LookAtRotationOnly_Y = Quaternion.Euler(transform.rotation.eulerAngles.x, LookAtRotation.eulerAngles.y, transform.rotation.eulerAngles.z);
        transform.rotation = LookAtRotationOnly_Y;