If you click on Settings -> Battery and device care -> Click on battery -> More battery settings
You will find the Adaptive battery. Enable it.
Hi, we would like to inform you that Battery usage time may vary depending on your device settings and operating conditions, or installed application lists.
You can view the estimated battery life based on how much you have used over the past week.
You can also closely monitor how much battery your apps are eating up.
From Settings, swipe to and tap Device care, and then tap Battery.
To view your battery usage, tap Battery usage at the top of the page.
Since the latest update which was pushed a few days ago, which was very large and mainly focused on Samsung One UI improvements, I've had major battery drain!
I'm also finding that my phone isn't charging as fast as it used to before the update.
Not sure it's what you're experiencing, but it's annoying!
Charging is fast again and battery holds the charge a long time.