OK - by hard reset, do you mean holding down the Power button until the slider control appears and then switching off?
Another approach that might work....return to the Home screen...now double press the Home button to open up the multi-task bar. Now press and hold any icon until they all start to jiggle. Now touch the upper left hand corner of the App Store icon to completely close it (doesn't delete it, just completely shuts it down).
Now see if the problem persists....
Tim