Ensure that the watch is connected to the phone using the NoiseFit app. Open the NoiseFit app and swipe down on the Homepage screen to sync data. If the issue persists, restart the watch and try again.
If you are still unable to sync data, close the NoiseFit app and make sure it is not running in the background. Open the app again and try syncing data once more.
Activity data is usually very large and therefore takes longer to sync. So Swipe Up from the Homepage screen and wait for the watch to be synced. The Syncing is displayed on the top in Percentage value.