I bought this to assist in my rehab after major surgery. The heart rate, respiration, sleep and pulse ox functions no longer work. The green lights on the back no longer work as well. I was in a lengthy chat session with Garmin support on Saturday that left my Venu SQ in worse shape than when I started. I'm not sure what I did, but I eventually got the display back, although with VERY limited functionality. The final result was a trouble ticket was opened with Garmin engineering(?).
I had similar problems back in June that were related to a software update that was not applied, even though I had automatic update enabled.
Now it looks like I will have to start looking for another fitness tracker, and the probability of it being a Garmin is very low.
Thanks for listening, rant over.