MissingReferenceExeption

Unity Engine
3

Firstly, please read this post on how to post code in the forum.

You can reduce nesting by simply returning if player is null, like so;

    private void FixedUpdate()
    {
        if (player == null)
            return;

        float posX = Mathf.SmoothDamp(transform.position.x, player.transform.position.x, ref velocity.x, smoothTimeX);
        float posY = Mathf.SmoothDamp(transform.position.y, player.transform.position.y, ref velocity.y, smoothTimeY);

        transform.position = new Vector3(posX, posY, transform.position.z);

        if (bounds)
        {
            transform.position = new Vector3(Mathf.Clamp(transform.position.x, minCameraPos.x, maxCameraPos.x),
            Mathf.Clamp(transform.position.y, minCameraPos.y, maxCameraPos.y),
            Mathf.Clamp(transform.position.z, minCameraPos.z, maxCameraPos.z));
        }
    }

So what is that actual error you get? Null reference exception and where is player defined?

Also, as you are just moving a transform and now a rigidbody, why not just use update?