To prevent erroneous operation, some models need a long press to the power button to turn off the power. If you want to turn off, please press and hold the power button for 1 second or longer.
For models which do not require a long press, please remove AC adaptor or all batteries, and then reconnect AC adaptor or set the batteries according to the user's manual. You can download user's manual by the following URL:
https://world.casio.com/manual/emi/

The problem cannot be resolved even after turning the power off and on again, there may be a problem with the product. In such a case, please contact our authorized repair center. Please refer to the support page from the following URL to find our authorized repair center in your country or region.
world.casio.com/support/changecountry/