it has been only used for 2hr(which can be ignored here) not 3 hr in almost 2 days not 3 days. it looks like device doesn't go to deep sleep state. would u accept a device which can only last for 3 days even if u don't use it for a minute? my lenovo a6000 has far better stand by time although it has only 2300mAh battery.
i hardly used the device. it is not acceptable. device idle, android os and android system are eating a lot of battery which means phone is not going in deep sleep state. u can compare the screenshot with ur note 10 and if possible share with me also.
The longer you keep your device in an idle state the lesser screen on time you will get because the processor and other background activities will eat into it slowly. I don't know about you but the last time I got 4 days of battery on my M30s my screen on time was around 5 hours only.. whereas if I use it extensively for a day I get screen on time of around 12 hours.