Something's wrong with the battery. Discharges very quickly, in hours. Need to recharge every day and keep charging all the time. Even being charged it manages to lose power in a day. It's either something wrong with the battery or a motherboard on the watch. Straps in relatively acceptable condition plus charger. Nothing else, no manual. Need to recharge before attempting to start. Myself I was using it for running daily for 30 mins using installed Strava, the reliability was patchy