I contacted Samsung anf they had me turn off both my watch and my phone, wait for a minute and then start them up again. After that, they synced. I'm sorry, I forget whether I was suppose to start them in a certain order. Hope this helps. @Gibbeloth wrote: I too just received my galaxy watch 3 and was able to find and download the Samsung health monitor app to my note 20 ultra and it displayed the very same message "no compatible watch found". I tried several times all to no avail and then took the next troubleshooting step of un-installing the app on my phone so that I could re-download it. Only I have yet to find it in the Samsung store or in the Google play store again. All of the info I have found says that my watch from T-Mobile is updated to support ECG but I have read that if your watch is not compatible or you are in a region that is not authorized to use it, it will not show up in your search of the Samsung app store, only I did have it on my phone for 3 days (non operational days) but I did have it until I un-installed. My watch 3 still has the app but not my phone.
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I have the Samsung Watch 3 and I bought the Health Monitor app on the Samsung store. When I open the app on my phone to activate the app, I get the message "No compatible watch found. The ECG feature requires a Galaxy Watch Active2 or later to work."
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