Hm, if you've doen the restart, reset, and deleted and then reinstalled the app from the App Store, the only thing left is a full restore.
This is the best Apple article I've seen for that. It is for an iPhone, and meant to move your stuff to a new device, but if you follow the steps for your iPad, using it as both the old and new device, it should work.
How to back up your data and set up as a new device
But, if you are still within the first 90 days of owning your iPad, give Apple Tech Support a call. It's free for the first 90 days, and if they mess up they have to fix it.
Restart: Hold down the power button until the power off slider appears. Slide it off. When the iPad finishes shutting down, hold down the power button again until the Apple logo appears.
Reset: Hold down the power and home buttons until the Apple logo appears. The iPad will reboot. This usually takes a bit longer than a restart.