It is strange that it does not do anything since they usually arrive with 60% of battery and start without problems. If you connect the charger and do not turn on the led intermittently it is advisable to charge for a few hours to see if the LED starts to blink always with the USB connector fully plugged in.
Finally try holding the power switch for 30 seconds. Release it and hit the button again three times. Finally, put the charger and turn it on again.
With the charger unplugged it takes 2-3 seconds of holding the power button on to see the LED light solidly.(no blinking) If the charger is plugged in, holding the power button for no more than 6-7 seconds should show boot activity on the LCD screen... Otherwise try the long press in excess of 20 seconds and then three brief presses and it should hopefully boot.