Juanita,
You seem to have a rounded rectangle with sets of double Anchor Points, as opposed to the Round Corner effect or similar. So the shape is fixed and cannot be changed by removing/reapplying the effect or similar.
You may scale proportionally if you wish the corner radius to change with the size, or you may Direct Select double sets of corners (such as (ClickDragging across) all four Anchor Points forming the rightmost two corners) and move them (horizontally) by the right amount to scale the rounded rectangle in each direction without changing the corner radius.
Or something else to obtain something else.