Had the same experience tonight. Went to bed with 80% of battery, woke up hour later because of the noise outside, wanted to check the time - watch was dead.. so disappointing. Is there something like an event log or similar, so I could check what the bloody hell had happened to it last night? Software is up to date, do not use any third party apps or faces, just leave Spo2, stress heart rate and location on. Don't tell me to turn them off, it's not what I got a watch for, to wear it as an expensive accessory.
