Hi schroedercpa,
We see you're having issues with receiving duplicate notifications, and we'd be happy to help out.
Have you been able to try restarting the iPad since noticing this? If not, let's give that a try. While it's a simple step, it can often help with odd issues that come up: Restart your iPad
If that doesn't help, try toggling notifications off for one of the affected apps (Settings > Notifications), and then toggle it back on after a few moments. Then, see if future notifications for that app are still affected.
If it still persists, try uninstalling, and then re-installing one of the affected apps: Delete apps on your iPhone, iPad, and iPod touch
As uninstalling will remove data from apps in most cases, be sure to try this with one that this would have a minimal impact on.
Take care.