Setup ECG app in Apple Health

I have an iPhone 15 and a series 9 watch. I’m in the US. The ECG function works fine on the watch, but it’s not syncing with my Apple Health app. Online instructions say to “Follow the onscreen steps. If you don't see a prompt to set up, tap the Browse tab, then tap Heart > Electrocardiograms (ECG) > Set Up ECG App.” There are no onscreen steps and there is no option to set up the ECG app in the Electrocardiograms section. How do I set it up?