Hi! The very first thing I would suggest is holding both the power button and the volume down button- keep doing so for 30 seconds or until it restarts.
If you're still getting nothing Press and hold the Power button for up to two minutes to shut down the device, Wait one minute, Press the Power button again to turn it on, If it's still unresponsive, charge it for 30 minutes.
Finally, make sure your charger works. As in, test on another device/ use a charger from another device.
I hope this is helpful. Let me know how you get along!
