Missing Method

hi there,
I'm new on unity. I tried to write a simple script for changing scenes. First, It was running, but now method is missing. Script and screenshot is here.

thx in advance

 

That's normal. If you were using something like:

public void ButtonThatGotDeleted()
{
Debug.Log("I will delete this then make a post on the forums later");
}

and then changed your script and removed that function, it will throw that error. Nothing to worry about, just press that error and select what you want your button to do