Before doing a factory reset open the tablet and disconnect the battery for a few minutes and while the batteries disconnected hold the power button down to remove any static discharge in the memory. If theres no joy after that then do the reset but remember you will lose all your data and apps . this reset you to factorey like it was when you first got it. This video shows how to open the back and disconnect the battery .you dont need to remove the battery just disconnect it.

https://www.youtube.com/watch?v=lcKIPddf...

Hope this helps