Since the last update the battery drain in less than 8-9h to 0%. Any solution

If you haven't , make sure you do a hard restart of watch (recommended after updates).  Press the upper left button for ~35seconds until the screen goes black and then turn back on.  

Thanks for the tip. But It doesn't work. I did that but it's the same.

Before the last update It was ok. Maybe wait for the next one because now the watch IS useless.

Same here. Seems to be caused by Polseox?

Similar here battery will not recharge either

I have the exact same issue. It worked very fine but since last sunday suddenly the battery drops from 100% to 0% within a day just using not even tracking any activity. I already factory reset it and it did not change anything.

The watch is unusable as is...

I have the same problem! Battery life used to be amazing but now it is terrible, can't believe I paid $500 for this? Charged it to 100% last night and now it's down to 90%, after just using it while sleeping? It goes down 25%- ish every day, even without tracking activities. I have the latest update, its been restarted, even to factory settings. It's been like this since like December sometime? 

See forums.garmin.com/.../troubleshooting-guide-for-high-battery-drain