If your Xiaomi Smart Band 8 has no heart rate monitoring record, please refer to the following steps:
1. Check whether the green light on the back of the band flashes when touching the skin. If the green light flashes, it means that the heart rate monitoring function of the band is turned on normally. If there is no green light flashing, please verify whether the heart rate monitoring is turned on;
2. Please wear it in the correct way. The band should not be too loose. Adjust the wearing method and then re-enter the heart rate function of the band to check;
3. If the skin is too dry, skin scars will affect the heart rate measurement;
4. Low winter temperatures will also affect the heart rate measurement;
5. If there are no above problems, you can restart the band, change an arm to wear it and try again.