I see that you're not receiving notifications for WhatsApp and Instagram on your iPhone after having updated to iOS 11. I'm happy to help.
Force an app to close on your iPhone, iPad, or iPod touch -- First, force close the Instagram and WhatsApp applications if they're open, then -- Restart your iPhone, iPad, or iPod touch -- Once it's returned to the Home screen, test the issue.
How to check the storage on your iPhone, iPad, and iPod touch -- If restarting your iPhone didn't resolve the issue, you can offload the applications, then reinstall them again. Go to Settings > General > iPhone Storage, scroll to Instagram first, and tap "Offload App". Once the application has been removed, reinstall it again and test. If you start receiving notifications for Instagram, do the same with WhatsApp and test.
Let me know how that goes.