At night, at least (twice?) now, I've powered off my phone around 60%.
The first time, I didn't even realize anything happened. I turned on the phone and it restarted... then turned itself off. It was dead.
This second time, I woke up and powered the phone on. I saw it opened up right where it left off around 65%.... however, within a minute, it dropped to about 30-35%. Then, the battery drained extremely quickly..... 1-2% every 10-20 seconds....... I plugged it in the charger around 14%, but it CONTINUED to drain down to 8%, when it finally started charging again.
Any idea what this could be?
Edit: Thank you very much for your replies.
An update with the situation. When I plug in the phone, it charges normally (fast charging cable). I use it normally. I downloaded AccuBattery to track the battery. Not really sure much weird stuff is being picked up by AccuBattery either. The battery drain only happens after I power the phone on after powering it off to go to sleep. During the day, it's basically a normal phone. It's extremely confusing. I did catch last morning the battery apparently using 1,890mA (-481.7%/hr) while plugged in and supposedly charging (which was not the case, as I was watching the battery drain although it was plugged in).