Frog only jumps but does not move forward.

private Animator playerAnimator; 
private float moveHorizontal;
private float moveVertical;
private Vector3 movement;

// Use this for initialization
void Start () {
    playerAnimator = GetComponent<Animator> ();
}

// Update is called once per frame
void Update () {
    moveHorizontal = Input.GetAxisRaw("Horizontal");
    moveVertical = Input.GetAxisRaw("Vertical");

    movement = new Vector3 (moveHorizontal, 0.0f, moveVertical);
}

void FixedUpdate() {
    if (movement != Vector3.zero) {
        playerAnimator.SetFloat("Speed", 3f);
    } else {
        playerAnimator.SetFloat("Speed", 0f);
    }
}