If "Individual" is one of the built-in category, then you will need to create a duplicate of it and (optionally) hide the original. This is because you can't edit the built-in categories.
If you go to the Manage ribbon and select "Categories" you will find the list of available topic/article categories. This is where you modify the category definitions. Selecting one of the categories on the left presents a tool icon from which you can perform various actions.
Have a look and see if you can get it working