When you edit a existing news appears the menu to add a news.
In my test I found that when I clicked to edit an existing news item the edit form was displayed with no data in it. However, upon entering data and submitting the form I found that the news item I had tried to edit was indeed updated. So the problem is just that the edit form isn't being populated correctly.
Created attachment 4205 [details] [review] Proposed fix
Created attachment 4211 [details] [review] proposed patch
Pushed, please test