Thank you.Taken from a source... try this Ruthanne
If your fire stick won’t turn on, you need to Disconnect the power cord on the back of the device or from a power outlet, then plug it back in. You can also use your remote to restart your device. Hold the Select and Play / Pause buttons at the same time for five seconds. Or, select Restart from Settings> Device> Fire TV menu. For more info visit the site https://www.firesticksolutions.com/fires...
https://www.ifixit.com/Answers/View/454785/Why+won't+my+Amazon+Fire+Tv+Stick+Turn+on
Yes it happened to me...I tried everything in the book!!My remote for my firstik was giving me some problems and now it won't start my fire tv. I replaced the batteries just now and it still won't work. I just searched the prices on Amazon for a replacement and the lowest is 17.99!