Battery issues

similar issue for my s21 battery don't even last for 12hr. even on power saving mode

when complained samsung is telling to update phone. but after updation its getting worse. even after 5 years my s7 edge battery is better than s21

I own S21 and the battery works just fine. try using dark mode it helps a lot.

am using dark mode from beginning but no use

I hope before you used the phone for the first time you let it charge to a 100%
Also, I hope you do not leave the charging cable connected even after your phone has charged.

You can try the following
Go to Settings > Apps > Select all apps one by one > Battery > here make sure under "Optimise Battery Usage" it says "Optimising Battery Usage" and not "Not Optimising"
You can change it to "Optimising Battery Usage" by just clicking it and switching the toggle
Next turn off "Allow Background Activity" for the apps you use the most

If the above does not help
Try Resetting and/or Hard Resetting your phone
Try using you phone in Safe Mode and see if the problem still occurs

Hope this helps 🤞🏻

sure i will try

Kindly be informed that Battery consumption depends on phone usage. However, to reduce battery consumption you can kindly try below advises:

• Turn off Wi-Fi to save the battery when not in use.
• Change the screen resolution. It is set to FHD+ by default. Higher resolutions make the display more vivid, however they will consume more battery power.
• Use Device Care. The device Care feature provides an overview of the status of your device’s battery.
• Change Power saving mode. MID: Activate power saving mode to extend the battery’s usage time. MAX: In maximum power saving mode. The device decreases battery consumption by applying the dark theme and limiting the apps and features available. Network connections, except for the mobile network, will be deactivated.
• You can save battery power by preventing apps that are running in the background from using battery power when they are not being used.
• Tick apps from the apps list and tap SAVE POWER. Also, tap MENU → Advanced settings and set the App power monitor options.
• Also if you are in a weak network area try to move to an area with a good network signal to avoid battery consumption.
Note: The battery capacity and lifetime will reduce if it is overcharged often, the battery can be charged and discharged hundreds of times, but it will gradually wear out. Battery charging time depends on the remaining battery charge and the type of battery and charger used.

sir i tried all these things. my issue is only while calling either video call or regular call phone is getting over heated especially below 60% battery and battery is draining too often maximum 1.30 hour call its getting empty. even my s7 edge, 5 year old phone is getting more battery than this sorry i am not understanding why its happening

same issue s20 plus.. what samsung gentleman mentioned is all done but while working normally like browsing, chatting or even calling battery drain too fast so it doesn't correlate this with any settings.
if most of the users in fact all users have same issue than definately there is something common issue.
i have purchased phone just 4 days back