I can’t enable blood oxygen on my watch

Try unpairing your watch from your watch app and install as new watch then make sure you have a good connection then pair it again and make sure your region supports the blood oxygen level.

I have installed iOS 14.5 and watch OS 7.4 and it worked :-). Try and let me know if anything comes up.

I thought it was a hardware issue but then when I added another watch to the watch app and during that process, I was prompted to install an update and when it was done the blood oxygen level worked on the new watch I added as well as the old one. I don't think what I did was the solution to the problem, that's why I thought it was the update but you can try and I hope it works for you.

Then try apple support. Apple support is not supported in my country but I hope it is in your country.

Yes, blood oxygen level app is available in my country, if not, it won’t be installed in the first place. Please, note that I have already tried re-setting my I Watch to factory settings and did the setup all over again with same result. I also tried reinstalling the app on the watch.

Thanks for the reply. Yes, my iWatch is series 6 and I have the latest software update on both my iWatch and iPhone. Could this be a hardware issue?

Apple support is not available in my country. Thanks for trying to help.

I have already done that resulting the same issue. That error message shows up during the set up process as well.