Hi; If your tablet device is locked and won’t turn on, here are what you will do;
Device Locked Power light is on but not on:
In this case, it is necessary to reset / restart the device. If your device is locked for any reason while it is charging, press and hold the power button for seconds. Your computer will shut down and press the power button again to restart.
My Device Will Never Turn On:
In this case, it is necessary to charge the device for a long time. When your device is not used for a long time, the battery can be completely exhausted and the battery can protect itself. You may also encounter this situation when you first purchase. All you have to do is plug your device into the charger. Charging time can be long. (Up to 24 hours) The device will charge itself even if it is slow. Unplugging and reinserting the adapter at regular intervals can speed up the process and shorten the charging time. You can then use your device normally.
You have tried these and if the device still does not turn on, you can take it in the service.