I'm S9 user and I'm facing the same issue since ages 😅. it drain faster than bullet train 😅😂. it's hardware problem. exynos chip is not very well optimized for battery life and we can't do anything except charge the phone.
try restarting it and check if it resolve the issue. and yeah i have seen many people with exynos chip have the same issue and if you scroll on community tab in members app you will definitely find someone as well. 😅
No idea man... it already released in Germany and within 2-3 days we get in India but don't know why this time we didn't get it till now... anyway I am disappointed with samsung that it is not going to provide is further update after this... In terms of that I like policy of Apple at least you can keep your phone for 4-5 years if it is not having any other problem