Dear Samsung Member,
Greetings from Samsung Customer Support!
Kindly follow the below mentioned quick steps an be assured that your issue would get resolved.
1) Battery optimization:
Settings > Select Device Maintenance/Device Care > Optimize > Optimize all options like Battery, Storage and Memory
For battery drain please follow the below link and perform the troubleshooting steps. https://www.samsung.com/in/support/mobile-devices/samsung-mobile-battery-drain-issue
If the issue still persists kindly attach the log file and send it to us in the Samsung member application(attach when the issue occurs within first 15 minutes):- Samsung Members App>Feedback >Question /Error>Attach log file.
Thank you for writing to Samsung.
Samsung Customer Support