Scroll down and tap Unpair device or Factory Reset .
From the watch face, press the physical side button to enter the app list.
just because a step counter seems inaccurate or a heart rate looks odd. Those are sensor issues, not software issues.
and "Forget" the device to prevent any connection conflicts when re-pairing. Are you planning to the watch to the same phone, or are you preparing it for a How to Factory Reset XIAOMI Redmi Watch 3