I went to bed around 1am. When I woke up at 8am, the phone was off. So then I tried to power it on but there were enough power. The phone still has at least 80% of battery before I put it to sleep while I was in bed. I wonder what could've drained it so fast. I mean the phone works fine for weeks before this, it's not a battery issue afaik since it could easily last days on standby. Anyone else experienced this? Is this a bug or what?