Before the watch has been paired with your smartphone, it usually doesn't show the correct time and date. Once paired, the watch updates the date and time automatically, in accordance to its geolocation, as soon as it connects to the mobile network.
You can choose between the 12 and 24-hour time format in the Settings of the watch > Clock format.
If you keep seeing the wrong date or time on the watch, check if the SIM-card has active mobile data and if the watch receives good coverage. Rebooting the device will help the watch to reconnect to the network and update the date and time.
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