Last night, my husband put my watch to charge and gave it to me two hours later and said it was fully charged. I put it on before bed because I like it tracking my sleep. Well, when I put it on, I realized it wasn't on. I turned it on and it was at 1% and died in 2 seconds. I asked him if he was sure it was just fully charged? He said it said 80% charged when he took it off the charger less than five minutes before.
This morning he put it to charge at 5am and took it off at 7am. I went to grab my watch on the counter at 10am and it was 80% charged. I put it on. It is now 11:32am and it has died on me. This watch used to last me 2 days fully charged and the last 5% would usually last me hours! Now my watch is dying within an hour? I don't know what to do or why this is happening. I'm not sure if this has anything to do with it, but I got a new phone (Samsung Galaxy S20 FE 5G) a few weeks ago and ever since I got it, there are times I get a random message telling me the Galaxy Wear app "stopped working" and gives me to the options to "wait," "close the app," or report it. I always just press close because my watch would be working just fine. What do I do? And why is this happening? I've had my watch for a little over a year. And have worn it almost every day since I got it.
There might be an issue with the watch because you have not changed the watch to which it is connected in the wearables app. There is a facility to change the watch to a "new phone." The reason your watch may be wearing down may be because it is constantly trying to locate the old phone and uses up a ton and a half of battery looking for a phone that you no longer have. I had that issue when I went to a Note 20 ultra and forgot to change the watch to my new phone. After I did that, no problem. My watch is a Gear Classic 3.