Thank you for reaching out. Are you using the original charger that came with the watch?
Have you tried plugging your charger into a different wall outlet?
If your watch's battery is completely discharged, it will not power on. You'll need to charge it before turning it on. If the watch will not power on or if it doesn't seem to charge, the problem could be anything from the battery, connection, the charger, or the watch itself. Give this link a try: https://www.samsung.com/us/support/troubleshooting/TSG01003100/