Losing too much battery in a short time

[He3dshot]

So i have a redmi note 9 proEU and im losing almost 30% in 3 hours while literally doing nothing intensive. Im just watching youtube.
Im on miui 14.0.3.0.

I will attach an example

 

[sir_bazz]

So i have a redmi note 9 proEU and im losing almost 30% in 3 hours while literally doing nothing intensive. Im just watching youtube.
Im on miui 14.0.3.0.

I will attach an example

Yeah. I just replaced my battery last week after experiencing the same. Wanted to blame software because it started happening after upgrading to miui 13.x a couple of months back, (and continued on 14.x), but the new battery has been good so far.

My device was a May 2020 batch so pretty much 3 years old.