1. There may be something wrong with the heart rate sensor of the smart watch, which cannot accurately measure the heart rate.
2. The heart rate sensor cannot accurately measure the heart rate due to incorrect wearing position or improper tightness of the watch.
3. The user's physical state is unstable, or the exercise is too intense, resulting in a large fluctuation of heart rate, which cannot be accurately measured.
4. The watch's insufficient power or signal interference may lead to inaccurate or unmeasurable measurement.
It is recommended that you try the following methods to solve the problem at runtime:
1. Make sure that the watch is worn correctly, in the right position and moderately tight.
2. Try to avoid too strenuous exercise and keep your body relatively stable.
Make sure the watch is fully charged to avoid signal interference.
4. If the above methods still fail, it is suggested that you contact Huawei customer service or go to the after-sales service point to check whether there is any problem with the heart rate sensor of the watch.