Ui system

you can ignore this one and go to one below----Im trying to make a ui that follows npcs and i got that far however i cant figure out how to make it stop calling null references when an npc isnt selected here is the code that keeps yelling null reference

Code (CSharp):

1. public SinglePlayer sP;
2.     public GameObject dBox;
3.     public GameObject selected;
4.  
5.     public void Update()
6.     {
7.         selected = sP.selectedNPC.gameObject;
8.         dBox = selected.transform.Find("DialogueBox").gameObject;
9.         bool inRange = sP.inRange;
10.         if(inRange == false)
11.         {
12.             dBox.SetActive(false);
13.         }else if(inRange == true)
14.         {
15.             dBox.SetActive(true);
16.         }
17.     }

the selected is calling the null reference but i just want it to only look for an object when it needs to not every time right now it spams null reference even when an object is inside of it so im confused everything else works tho

 

i updated it to this i got rid of null reference but now it chooses every single DialogueBox in the game and makes them active i only want the one that is selected to be active

Code (CSharp):

1. public SinglePlayer sP;
2.     public GameObject dBox;
3.     public GameObject selected;
4.  
5.     public void Update()
6.     {
7.         bool inRange = sP.inRange;
8.         if(inRange == true)
9.         {
10.             selected = sP.selectedNPC.gameObject;
11.             dBox = selected.transform.Find("DialogueBox").gameObject;
12.             dBox.SetActive(true);
13.         }else
14.         {
15.             dBox = this.transform.Find("DialogueBox").gameObject;
16.             dBox.SetActive(false);
17.         }
18.      
19.     }

 

Nah Nevermnd i figured it out lol