Kindly reset factory data with backup then try to it's again. If you like please accept it's as a solution it's help to other users also, click on 3dots in my reply section and click on accept solution. Thanks.
It's a universal problem with OneUI8. Even in our Ultra series, normal RAM usage goes to 8GB which was never the case in OneUI7. Sometimes RAM usage goes upto 9.6GB. Samsung mast chu bana raha hai...
