Deleting app data from settings

Hi. When I try to delete app data within the manage my storage area! I can't seem to delete app data. Even when the screen within each app shows that I have deleted the app data! I still see that it hasn't succeeded with the task when I return to the list of apps that show you how much space they are taking up. For example.! My Audio Boom app is taking up around 200mb of space and 130mb is made up of the extra cash it's accumulated and swiping up on app data gives you a choice to delete app app data and voiceover tells me that I've deleted it. As I've pointed out above! returning to the previous screen still shows that the app is taking up 200mb. I've tried deleting data from other apps and I'm getting the same result.