We should have how to google classes or something..
You are right I shouldn't have said that.
I should have said that : I have already googled but what I have found didn't help me out to solve the issue
Power Button Lock
This mode locks the power of the LCD dislay in the ON position.
• Power Button Lock: Press and hold  and the down arrow for 10
seconds. If the power button is pressed the message Power Button Locked
will display for 5 seconds. With or without this setting, after a power failure,
your LCD dislay’s power will automatically turn ON when power is restored.
• Power Button Unlock: Press and hold  and the down arrow again for
Yes I did find that and I did try it as below :
I tried to hold down power button for about 30 sec no joy
I tried to press power button and upper arrow button still no joy
What would be other suggestion I should try ?
Still I am waiting for alternative solution