Next book keeps turning off on its own

[devonandkayla16]

The only apps I have are Facebook, messenger, Hulu, YouTube & weather. The rest were already on my next book.
I hadn’t messed with for several months. I had it turned off & stored in its box until these past few days.
It’s fully charged but every time I turn it on, it shuts off on its own. By that I mean, as soon as I swipe to unlock it, it turns off.
I read that turning it onto safe mode could possibly fix it. I did as the post said but it doesn’t have a safe mode option. The options were normal, recovery, FTM, and several others but I can’t remember all the other options. Which one is “safe mode”?
What else could be the problem?

 

[Saga Lout]

The "fully charged" message could be wrong if it was off for several months. If you can remove the battery, do so then hold down the power button for a few seconds to release the flea power.

Then turn on and see what happens.