inconsistent battery drain

Hi, i have a apple watch series 4 that still has 90% battery health, since I updated it to WatchOS 9.2, im facing an issue with its battery usage. 2 days since the update, the battery would last only 7-9 hours (without any workout), then it back to normal again for a few days where I can get 1-2 days of use, but now its draining quickly again, i dont understand what is happening here does anyone had similar issue with this? Ive tried to unpair and pair the watch but it seems didnt change anything, thanks

here you can see how quickly the battery drained then after i charge it somehow it was back to normal again