I think I know what the problem is. The smartphone's software is dying out BADLY. Trust me, this sort of thing happened to me before, but honestly... it seems your case is much worse. The only solution is to get a new smartphone and have ALL of the data saved on it transfer to your new smartphone.
sorry that your phone's not working, have you tried turning it on and off?
I tried that and restarting it.
Alright, when my mom's old phone stopped working she also tried taking the battery out, if you haven't tried that yet.
You can't do that easily with a cover that can withstand a forklift.
Wow, still...give it a try if you can, that also helps when it overheats depending on which type of phone you have.