How come my NullReferenceException won't go away? [C#]

The error: NullReferenceException: Object reference not set to an instance of an object
Mining.Update () (at Assets/Kingdoms/Scripts/Mining.cs:34)

In the screenshot below, it shows that I have my Text variables that are assigned within the inspector to some text on screen, this works as tested by the Iron and Silver variable numbers being shown on screen from the script but they won’t update and when I try, it doesn’t seem to work.

I understand that it needs something to reference, but I have already referenced it. I have tried referencing it within the Start() and OnAwake() functions before the Update() function but it didn’t do anything.

any ideas? Am I just being stupid?

Fixed the issue. I had two of the same script active at the same time, thus causing it to render both unusable. It is all working now.