Roll a Ball tutorial

I am trying to do the roll a ball tutorial and when i write the script word for word like the tutorial I get the error…

“The class defined in script file named ‘PlayerController’ does not match file name!”

this is my code

using UnityEngine;
using System.Collections;

public class PlayerController : MonoBehaviour

{
			void fixedupdate()
		{
			float moveHorizontal = Input.GetAxis ("Horizontal");
			float moveVertical = Input.GetAxis ("Vertical");
			
			Vector3 movement = new Vector3 (moveHorizontal, 0.0f, moveVertical);
			rigidbody.AddForce (movement);
		}
	}

please help
Thanks

In C# the name of the script file must match the class name. So in Unity, you need to rename the file that contains this script to ‘PlayerController’.