1. Please keep wearing the watch correctly. Note that do not wear the watch on the arm with tattoos, as this may give an incorrect reading.
2. Take off the watch and put it back on to measure again.
3. When measuring your heart rate, check if the indicator light on the case back is flashing. If it is not flashing, press the button on the Watch 3 Pro to enter Settings--System Menu, then click Restart. Or, long press the button, then click Restart, and check again.
4. To experience the latest firmware features, you can upgrade the firmware to the latest version in the Nothing X app. To do this, open the Nothing X app, go to the My Devices > About > Firmware update.
5. If the above steps do not resolve the issue, press the button on Watch 3 Pro to enter Settings System Menu. Click Reset. Then, check again to see if the issue is resolved.
Note: Overstretching of muscles can also lead to inaccurate heart rate data.Therefore, there is a low probability of inaccurate heart rate readings when performing arm strength training.This is a common issue with all heart rate sensors. It is not a product quality issue, so you can use the Watch 3 Pro with confidence.