View source for Changing a Categorie of a page after it has been created

I go to the edit page properties that I have open and select Categories to edit 
the categories of the page in question. I deselect the check box for the category that page was in only leaving 1 category.
click save category, and it looks like the changes did not save. the page is still in the two categories
So thanks for any help
Wackowiki has been great to work with.