Apple Watch ECG app

1.Restart phone and watch.

2.Turn bluetooth off on phone and watch,then turn them back on again.

3.Clean the digital crown and sensors on the bottom of the watch.

4.Uninstall and re-install the ECG app.

5.Setup the health app;

Open the Health app and tap on the Summary tab.

Then, tap Heart. After that, tap Electrocardiograms (ECG).

Click Set Up ECG App and follow the onscreen instructions.

If you don’t see the app on your Apple Watch, you can search the App Store on your Apple Watch for ECG and download it.

6.Reset the health app settings;

On your iPhone;

Settings/General/Reset/Reset All Settings.

Tap on Reset All Settings.

This will erase your settings (without losing any data) and will allow you to re-setup the health app and re-enable the ecg app.

Be aware though that this will delete any cards setup in apple pay.