It could be the tablets software or it could be the battery, even other hardware.
To try and do a reset, try the following. NOTE: If you choose the "Wipe data" option when selecting what you want to do, it will wipe everything on the device and there is no way to get it back, so be sure you really want to try that option, should it be the one you select.
1. Make sure that the tablet is actually powered off.
2. Remove your SD card, if there is one in the device.
3. Press the "Power" and the "Volume Up" buttons, together, until you see the start-up logo on the screen.
4. Once you can see the logo, release the buttons and allow the device to enter the "System Recovery Mode".
5. Next use "Volume Down" button to get to the option you wish is highlighted. When in recovery mode the "Volume Up" and "Volume Down" buttons are how to can navigate and highlight what option you need.
6. Once you have selected the option you want, press the "Power" button to select that option.
7. On the following screen, repeatedly press the "Volume Down" button until the the option you wish to use is selected.
8. Then press the "Power" button to hard reset the tablet.
9. If you took your SD card out in step 2, when the device is up and running again, reinsert the SD card.