I don't know what happened but on my 5 the first day was normal, I had around 50% at the end of the day and then the next day I had 1% 3 hours before I go to bed. This NEVER happend in the year I have this watch. I enabled the had washing notification though. Maybe that is the problem? I have no idea how to turn it off though. I can not find the option in the iPhone health app anymore.