Originally Posted by firstname.lastname@example.org
The device was bought from Amazon, not a 3rd party, and it was working fine until my mom let it sit for several months without charging. Which should not have been a problem, but facts sho otherwise
You should pound on Amazon for a replacement - especially since they falsely accused you of having a rooted device (how do they know that?). I'm guessing the device may have received an 'over-the-air' upgrade while it was sitting idle but perhaps lacked sufficient charge to complete the update. Or the upgrade just went bad; rare but it happens.
Sorry this happened to your mom. Also regret there is not a (reasonable) way to recover the device and/or its contents.