Last night I went to bed with 2 alarms set on my htc one m7 which I had just taken off the charger after fully charging. I woke up an hour after I had to be to work and the phone was off and completely dead.. I even double checked to see if it was charged before going to sleep and now I may have lost my job. It has been a great phone so far and the battery has never discharged like that before and seems to be working fine now. Has anyone heard of this?