Object reference not set... but... it is?

So I'm getting an error saying that my GameObject "item" isn't set to an instance of an object. I don't understand what the problem is. This is the line with the error (I'm trying to print the item's name as a test):

     public void displayItemDescription(float width, float height) {
         
         Debug.Log(item.name); //error highlighted here, ignore other stuff for this case.
         
         GUI.Box(new Rect(0, 50f + (height - 250), width, height), "" + itemDesc);    
         
     }

The GameObject item is set to public so I can see when the item changes depending on what button is being hovered over. The changing of the item variable happens in this code:

             GameObject goItem = (GameObject) item;
             
             if(inButtonArea(px,py,75f,75f)) {     //a function for checking if hovering.
                 
                 player.GetComponent<CraftMenu>().item = goItem;        //set current object to item in other script
                 
             }