Please embed screenshots in your posts.
I don't get what you mean..? The screenshot you posted has the individual corner radius selectables available..?
Highlighted here (your screenshot):
the fields are not locked, so it must not be a problem to change them separately. What happens when you set different values?
Do you have a shape highlighted?
If you draw a new rectangle, it should appear.
If you inadvertently changed the shape of that rectangle even minutely - the radius will not appear - only works on perfect rectangles.
Hope this helps,