Yep. Just ran in to this problem. My 40mm active watch is 2 months old. This morning the back came off. It has only been exposed to perspiration. I called the warranty service folks and was told that it could be water damage and that I would have to pay. They wanted a $107.00 hold on my credit card in the event that their technician determined that I had damaged it, which is outside of warranty.
I scoffed. I asked them to send me a list of their criteria to determine damage. I pointed out that the watch cost 190.00, why would I spend 107.00 to repair it?
Based upon what I have read, it turns out this watch has a design flaw and Samsung doesn't "back it". <<Pun.
Also, what's with the "water damage" thing with a watch that is supposed to be used in the water?
Until Samsung fixes this problem, there will not be another one of their watches on my wrist. I'll just krazy glue it and hope for the best.
Two months of use, and it breaks. Buyer beware.
My watch became completely unresponsive after a week of very light use. I went swimming in it one day in a shallow above-ground pool and that did it in. I've had $35 Timex watches since I was a kid that resisted diving 8-10 feet deep with Zero issues. I'm overwhelmingly dissapointed that this thing couldn't even handle basic water exposure despite being advertised as a watch you can swim in (you know for exercise? the thing the watch is supposed to be specifically for??). This will probably send me back to Apple for keeps now. Before this, I had a series 1 Apple Watch which is NOT waterproof that I've swam with, taken showers with, etc, with NO issues.