Hi @Wrightacus,
A drop in battery life after an update is often normal. A major update can cause temporary instabilities because the system, having to process a large amount of new information in a short time, keeps the CPU and internal resources constantly active. This leads to a temporary increase in consumption but, once the new instructions are "learned," everything tends to stabilize.
To help speed up the stabilization, we recommend performing a wipe cache partition. This procedure is safe, it does not delete photos, videos, apps, or messages.
1. Completely turn off the smartphone.
2. Connect the device to the computer via a USB cable.
3. Press and hold simultaneously the Power and Volume Up buttons.
4. When the "Samsung" logo appears on the screen, release only the Power button, continuing to hold Volume Up.
5. Wait for a blue screen with the Android symbol or a warning message to appear, then release the Volume Up button as well.
6. The recovery mode menu will appear: use the Volume Up and Volume Down buttons to scroll through the options.
7. Select "Wipe cache partition" by highlighting it with the volume buttons.
8. Press the Power button to confirm the selection.
9. On the next screen, move to "Yes" using the volume buttons.
10. Press the Power button again to confirm the cache wipe.
11. After the process completes, the recovery menu will appear again. Select "Reboot system now."
12. Press the Power button to restart the device normally.
