To prevent the watch from losing time, please ensure the Auto Sync feature on your COROS watch is turned on. With Auto Sync, the time on the COROS watch automatically updates to the time on your connected smartphone. Please follow the steps below on your COROS watch to turn on Auto Sync.
main watch face > System > More Settings > Date/Time > Auto Sync > On
Please submit data via the COROS app (Profile page > Submit Data > Send) and contact us at email@example.com if the time does not update.