How to fix
What is Child Lock?
:If you choose to lock the buttons on the control panel
to prevent tampering with ongoing cycle. Select this function.
Child Lock can be set by pressing the PRE-WASH(*CHILD LOCK) or
TUB CLEAN(*CHILD LOCK) for 3 seconds
When Child lock is set, all buttons are inoperable except for power button.
(Some new models including power button).
To unlock Child Lock system, press the same button again.
Selection methods could be different by Models.