Space Shooter Tutorial Player Won't move.

At lesson 5 I can't get the PlayerController.cs script to work, i can run the game , no compiler errors but also no movement; Here is my code: At lesson 5 I can't get the PlayerController.cs script to work, i can run the game , no compiler errors but also no movement; Here is my code:

 using UnityEngine;
 using System.Collections;
 
 public class PlayerController : MonoBehaviour {
     private Rigidbody rb;
 
     void Start () {
         rb = GetComponent<Rigidbody> ();
     }
     void FixedUpdate () {
         float moveHorizontal = Input.GetAxis ("Horizontal");
         float moveVertical = Input.GetAxis ("Vertical");
 
         Vector3 movement = new Vector3 (moveHorizontal, 0.0f, moveVertical);
         rb.velocity = movement;
     }
 }