ECG Fix!

Along with a lot of others here, my Apple Watch 7 ECG app stopped working. I spent an hour on the phone with an Apple service guy unpairing/re-pairing etc. and eventually he got me to send it to Apple. They sent a replacement watch 7 (different s/n) and, after restoring from my backup (which involved updating the OS to 9.5.1) it behaved the same, i.e. ECG didn't work.

That's what brought me here, where I found one thread that suggested disabling: Settings>Accessibility>Assistive Touch. I checked and mine was already disabled, but figuring I had nothing to lose, I enabled it and reset the watch and ... it worked! My ECG app is again functioning. I have since disabled Assistive Touch and everything still works.

I'm not sure what, exactly, fixed the ECG because I enabled Assistive Touch in Settings on both the watch and the iPhone and I forced-reset the watch. It may be sufficient just to toggle the Assistive Touch setting on the watch. It may or may not need the iPhone to be involved and you may or may not need to restart or reset the watch, but I'm certain the problem is somehow connected to the Assistive Touch setting.

Good luck!