Sorry for not responding soon. Strangely, exactly the same question came up at the Brisbane course last week.
The simple answer is that you have the Peak Areas graph showing "Peak Area CV" on the y-axis. A CV is standard deviation / mean, which means both values are used to show the bar and there are no whiskers to show. It sounds like you want to be showing the mean area and whiskers for the standard deviations.
To get that, just right-click the graph and uncheck "CV Values".
Thanks for posting the screenshot to the Skyline support board.