How recently did you obtain the phone? Have you updated your device recently?
Galaxy phones have an adaptive battery feature that uses machine learning to optimize battery consumption based on your usage.
When the phone is new or after a major software update, this feature resets and needs to relearn your usage patterns. You may notice diminished battery life for a week or so while this process takes place.
Have you performed these steps for routine maintenence?
โ Follow Samsungโs Best Practices Guide
In particular, clearing device cache is an important practice in order to clean up junk files and keep things running smooth.
Download Good Guardians and run its various modules. These modules optimize performance and can identify unusual behavior. App Booster, Memory Guardian, and Battery Guardian specifically will likely be helpful in your case.
