Hi there! I understand you're having trouble with the Lefun Health app not allowing measurements. Let’s explore some steps to get this sorted out.

1. Check Bluetooth Connection: Sometimes, connectivity issues can prevent the app from functioning correctly. Please toggle Bluetooth off and then back on your iPhone. You can do this by going to Settings > Bluetooth. Once you’ve done this, try reopening the Lefun Health app.

2. Restart Your Devices: Restarting both your iPhone and the device you’re trying to measure with can often help. After restarting, reconnect the app to your device.

3. Ensure the App is Updated: Make sure that you have the latest version of the Lefun Health app. You can check this in the App Store by searching for the app and seeing if an update is available.

4. Grant Necessary Permissions: Sometimes, the app might require specific permissions to access features like health data or Bluetooth. Check the app's settings on your iPhone by going to Settings > Lefun Health and ensuring all necessary permissions are enabled.

5. Calibration or Settings in the App: Depending on what you're trying to measure, the app might require you to configure certain settings. Open the app and look for any prompts or settings that pertain to measurements.

If you've tried all these steps and the issue persists, it might be a deeper technical issue that could require support from Lefun. You can also consider reaching out to Lefun Health's support at [email protected] for further assistance.

Finally, if you still experience problems, let me know, and we can dig a bit deeper together! Are you satisfied with the solution I provided?