iOS 11 banner notification problem

The new iOS 11 have bringed issue in to the iphone users that after upgrading iphone to iOS 11 banner notification aren't working. The problem is also faced with third party application like whatsapp. The problem is seen when the user have disable notifications on lock screen, now when some notification comes from some app and user unlockes the iphone, banner notification are missing from top of the iphone. However the user can see the notification of the app icon. This was working fine with the earlier iOS version ie iOS 11 and iphone 7/7s models, but with the iOS 11 iPhone Message Notification Not Working.

This is pretty annoying, since I chose not to have notifications on my lock screen, and need my notifications when I unlock my iPhone. Same issue is reported with email notification on banner of iphone. The iphone banner will say your have 10 new messages but no content shown. The problem even persist in iphone 8 and iOS 11.1.
iphone 8 notification not working.

Workaround for the iPhone banner notification issue:

This seems to be glitch in the new iOS 11 updated where banner notification are not working as expected.

But it looks like that if you chose one among history or as banner one of them will work. eg When in Settings/notifications/Whatsapp turn on show in history and show as banner they only show in history. And when turn of show in history and turn on show as banner, when i unlock  phone there is only banner and no history. Hopefully this one help you to fix notification as per your requirement whether in history or banner of iphone.