Here is my usage from some days ago. Mostly i unplug at night and lasts till next night. Not charging overnight also helps and lets the battery settle.
There were some articles and videos(like mrwhosetheboss) where using different methods to use to have a happier battery. Charge about %18-%87(depending on your taste.), Dont charge overnight, dont use fast chargers unless you are in hurry. I use a non warp charge supported cable(the ones which have magnetic type c plug. Mine is baseus 100w magnetic type c cable.) with original wall adapter since i bought the phone and i never had less than 7h sot.
Charge slow as much as possible, balance between min and max capacity(like 15 and 90 or 85. New samsung tablets has a feature where you select the option to not use %15 of the battery. Same as that.) and having it settle over night improves battery life, this is one of the reasons why i get good battery life with my gpu config + charging habits.
Think of it filling a baloon slowly, slowly but steadily makes it calm and happy, filling it fast makes it warm up a little and force it's shell. (Wierd example but meh, you get the idea.)
If you are sure no app is draining your battery, try these. Also check 4g band coverage. Sometimes if you get bad cellular signal your phone switches between bands which also might drain your phone overnight.
You might try setting 3g overnight with data on and try having 4g but data turned off. Also volte and vowifi helps a lot in this...
Hope this also helps for those who has battery life issues. Trying to give tips on this issue anywhere i can when i have time. Been using this charging method since my old s9+ times. Discovered this result when i had it and had to charge from a pc usb for a week cause i lost the charger. It was a good find lemme tell you that haha
I promise you if you use the slow charging method with no overnight charging and only %15-85ish for a week, i expect you to click the thanks button next week when you see the difference.
(This is how much im sure of myself. It will work %100 unless you have a hw issue somewhere or have software related problems.) Take care of your battery and phone. Treat them as your beloved pets since these are our daily companions everywhere...
Treat them well and they will treat you well in turn. Like how the world works(most of the time :c)
Mrwhosetheboss Youtube Video Regarding Batteries. Around time 02:50 he explains it very well. Fast charging causes stress, slow and steady charge causes more stable energy transfer = filling battery better and more efficient. After watching it, factories shipping phones around %50 give or take to shops at same release years will make sense to you. It is more healthier for the battery. If you recieve your phone out of the box with less than %20, know that your phone was on the shelf for a long time, "phantom drain" is not that high for a closed phone out of the factory imo. I always got my phones around %30-50 in half a year to 1.5 years prior to release date.