Galaxy watch 7 sleep stages stopped working properly

[Yiftach]

I use my galaxy watch 7 for about a month now. in the first 3 weeks the sleep tracking seemed to work great (see snapshot for example ).
But In the past few days it seems that something went wrong. The sleep stages no longer make sense. Too many flat areas, and sometimes the sleep time is split into 2 periods with no apparent reason (This was only shown on the watch), and only one sleeping cycle.
See here for example:

I set the sleeping mode on and off manually when I go to sleep and when I wake up.
I also set the watch on flight mode when I sleep, but that was all along, when it worked fine as well, so I don't think it is related.

Anyone knows what could be the problem?
Thanks

[JordanS · Accepted solution]

For accurate sleep tracking, make sure the watch has a snug fit overnight, and you have your Heart Rate tracking set to continuous under Samsung Health > Settings > Heart Rate. It's worth giving the sensors a good wipe down and if you haven't restarted your watch in a while, give a restart. 

[sonic47]

Have the same problem. First watch 7 purchased early December with that problem. Took back and had replaced and same problem with new one. Have written to Samsung via Members app to complain, suggest you do the same. I believe that its some sort of software problem with the watch, so the more complaints they get the better. They may look into it.

[RNA]

This is indeed some software issue, I am facing after recent Watch 7 SW update. 

[Members_0P2adNP]

Just been through a full reset with technical support but not holding out much hope.  I upgraded from a Watch 4 which reported the sleep pretty accurately, but the watch 7 either doesn't report anything, or it has blocks which don't make sense.

Very disappointed.

[Missty]

I just purchased my Galaxy 7 wat h and the sleep Recording has worked 2 out of 7 days. I've troubleshooted, no better. I click on sleep and it just spins like it's loading, but I never get results.  Sounds like it's a known issue. Very disappointing as that's one of the main reasons I bought it for

[Scottydxb]

Same issue with my watch 7, it's missing around 1 and a half hours sleep every night. The strange thing is that I have also downloaded Sleep Cycle and that is recording all of my sleep. Definitely a software issue.

[Members_RQr3zDI]

REMOVE THE STICKER THAT COMES ON THE WATCH'S BACK!

This may sound very dumb but it was the sole reason sleep tracking was broken on my Samsung Watch!

At least in my country, the Watch comes with a small factory ticket underneath it. And, although not totally, it was covering one of the green LEDs partially.

Now, I didn't remove the sticker initially because I wanted to keep the device pristine (since I had 14 days to return the device, should I wanted to). And I never thought about the sticker again...

I was having sleep tracking issues always, I was reading all the amazing tips online and was desperate.... until finally one day I was going to charge the Watch and there it was... the sticker looking and laughing at me... 😒😒😒😒

I removed it and it works flawlessly!

I hope this helps others as "dumb" as me 😄😄😄