Ensure you have left the tablet to charge for a minimum of 1 hour in case the battery charge level was too low to indicate that the tablet was charging.
Please press and hold the power button for at least 10 seconds (this performs a soft reset in case the battery has run right down to 0%). Then press it again to boot the tablet.
Try charging the Tablet from a USB power source and see if the charging light or on screen charging indicator appear. Leave it to charge for a minimum of 1 hour.
If neither of these solutions appear to resolve the issue please contact our Support Department.