Can't call methods in other scripts in Build

Everything works perfectly in the Unity Editor, but when I push to a build version, everything that involves calling methods in other scripts breaks.

I’ve been using the method of:

public GameObject goalTrackingEmpty;

goalTrackingEmpty.GetComponent<GoalTracking>().orangeScores();

where goalTrackingEmpty is an empty GameObject with GoalTracking.cs attached to it. I did it this way because I didn’t want to make everything static, but for some reason it’s just refusing to work in the build version of the game. I checked the error logs and I see this:

NullReferenceException: Object reference not set to an instance of an object
  at GoalTracking.orangeScores () [0x00000] in <filename unknown>:0 
  at BlueGoalDetection.OnCollisionEnter2D (UnityEngine.Collision2D collision) [0x00000] in <filename unknown>:0 
 
(Filename:  Line: -1)

which doesn’t really tell me much.

No idea why, but it’s fixed now. I think it was something to do with a missing link to an AudioSource object on one of the GameObjects in the scene ¯\(ツ)

I apologize to anyone who stumbles upon this thread hoping for a better answer.