Why won't my tablet turn on!?

So my parents just recently got me a Lenovo tablet a2107 and it glitches out and freezes so usually I just click the button on the top and turn the screen off and then turn it back on and it's fine, unfortunately I turned the screen off and now my tablet won't turn back on, I tried all of the 20 second bullshit button holding and it isn't helping! Please help! The screen is completely black and no buttons that I'm pressing are doing anything at all!