A good way to unstuck them is to lock the phone, unlock it and then hold the camera button down and the you can minimise that. That gets you back to the home screen
Do you have Swipe to Unlock enabled? If so, turn your screen off and swipe up from the bottom bezel. It might be a hardware problem. If the Swipe to Unlock doesn't work, you'll know that's the case.
Does this happen with all your apps? Have you tried a simple reboot? This helps fixing a bug most of the time. Hold down both volume buttons until the BlackBerry logo shows up.
Ya swipe to unlock is enabled. And i just do click and unread message in notification so that it enters the hub. And now the app automatically need to b minimised. This what i do now to recover from this
problem.
Back up and restore takes a long time in general. But if that's the only option you have left, I would advice you to do it. Your user experience now is screwed, because you can't leave an app without going in circles.
The lock screen doesn't need the bottom bezel. Try it out. If you swipe up from 1cm (+- 0.5 in) above the bottom bezel it will still unlock. Apps do need the bottom bezel to minimise.
It can be rectified by reinstalling the os rather than wiping? Or is that the hardware problem?
From My Z10
You can try both. Try to reload the OS from BlackBerry Link. If this doesn't happen do the security wipe. If both don't work, you should get it repaired or replaced.