Why isn't my Z10 device lock functioning?

I have a password device lock system. Soon after charging, it switched on, I attended a call on urgent basis and then "turning off device" notification popped up and the screen had unusual ray of colors and turned off.
After charging and switching it on again, I am unable to open the device now. The usual screen is coming up, the prompt box asking for the password is there but the keypad is not popping up

How on earth do I enter the password to open it den. I rebooted, restarted , checked the software - Nothing at all worked!!

If someone is calling, they can hear the ring tone, where nothing is being displayed on my screen, no one can bbm or watsap me too

PLEASE HELP!!!!!

Try the two finger swipe up from bottom to activate the keypad. Also try and get a backup done on Link.