Character does not jump

Hi, I just started using Unity and I'm having trouble finding the answer to a problem I'm having. My character won't jump and I can't find anyone else having the same problem. This is all the code that I think is relevant to the problem:

Animator anim; bool grounded = false; public Transform groundCheck; float groundRadius = 0.2f; public LayerMask whatIsGround; public float jumpForce = 700f; // Use this for initialization void Start () { anim = GetComponent<Animator> (); } // Update is called once per frame void FixedUpdate () { grounded = Physics2D.OverlapCircle (groundCheck.position, groundRadius, whatIsGround); anim.SetBool ("ground", grounded); anim.SetFloat ("vspeed", rigidbody2D.velocity.y); float move = Input.GetAxis ("Horizontal"); anim.SetFloat ("speed", Mathf.Abs (move)); rigidbody2D.velocity = new Vector2 (move * maxSpeed, rigidbody2D.velocity.y); if (move > 0 && !facingRight) flip (); else if (move < 0 && facingRight) flip (); } void update () { if (grounded && Input.GetKeyDown (KeyCode.Space)) { anim.SetBool ("ground", false); rigidbody2D.AddForce (new Vector2( 0, jumpForce)); }

Any help appreciated.