Have you rebooted your watch? Have you checked the Samsung Health on your watch, and does it have any data? If not, I would think it's an issue with your watch and not the app on your phone. Don't have a solution other than clearing cache and trying a reboot if you haven't already.
My watch is recording sleep time during the day when I'm awake! I know I was chilling out on the couch on Christmas eve but I wasn't sleeping 8:30 am to 4 pm! What's going on?
