I've been trying to figure this out for weeks.
I'll have my phone on, and the battery will say 80% or 65% or whatever. Randombly, my phone will die, and when I try to turn it back on, it says it has zero percent left. I have to start charging it for a minute, and the when I turn my phone on, it will say the initial percentage minus around 10 (e.g. 65 to 55, 80 to 70, etc.). Usually the phone only lasts for a little while.
My phone has no damage, as far as I'm aware, and is entirely up to date.
It's an Xperia Z1S. I have a 64 gb sd card plugged in, but it's only around 60% full and without it in, the problem persists. The problem still occurs even if I'm in airplane mode, although it seems to last longer. Safe mode similarly has no effect. I haven't done a hard reset yet but I'm considering doing so, even though I would REALLY prefer not to. I have a case on the phone, which could have something to do with the heat, but I carried the phone without a case and the problem still occured.
I'm super lost, any help would be greatly appreciated.
