Velocity Issues: First Character Controller Unity 2D

I cannot seem to figure out how to get my script to accept the velocity variable. I’m following an old guide, and it doesn’t tell me how to use the rigidbody.velocity in Unity 5. I’ll put my code below but if you can help could you explain why something goes somewhere? Any help is appreciated, thanks

public class CheekzController : MonoBehaviour {

	public float maxSpeed = 11f; 
	bool facingRight = true;
	private Rigidbody2D rigidbody; 

	// Use this for initialization
	void Start () {

		rigidbody = GetComponent<Rigidbody2D> (); 


	// Update is called once per frame
	void FixedUpdate () {

		float move = Input.GetAxis ("Horizontal");

		rigidbody2D.velocity = new Vector2(move * maxSpeed, rigidbody2D.velocity.y);

		if (move > 0 && !facingRight)
			Flip ();
		else if (move < 0 && facingRight)
			Flip ();
	void Flip ()
		facingRight = !facingRight;
		Vector3 theScale = transform.localScale;
		theScale.x *= -1;
			transform.localScale = theScale;
	} }

Only thing I can see wrong with this is that you have made variable called rigidbody, but you are trying to change velocity for variable called rigidbody2D that doesn’t even exists in this script. This should simply give you constant errors in console that says what is wrong.