What should I do if I cannot register the Zepp app?

Check whether the user account and password you enter are correct.
1) In the phone's settings, switch the network from Wi-Fi to 3G/4G network.
2) Clear the Bluetooth shared data and app cache/data.
3) Restart the phone.
If the above steps do not work, please uninstall the app and try to reinstall it from the Google Play Store/Apple App Store. If the problem persists, please contact on the official website https://support.amazfit.com/en/ticket/create.