Extreme idling battery drain (-70% overnight)

[Android Central Question]

Phone: Sony xperia X compact (bought in 2018). Android 8.0.0.0
Extreme idling battery drain (-70% overnight). This happens with the following ON and OFF: wifi, plane mode, bluetooth, stamina mode.

 

[belodion]

What did your battery usage stats indicate as the cause?

 

[ValerioRenna1]

What did your battery usage stats indicate as the cause?

right, I forgot to specify that.
inactive phone: 20%
android operative system: 16%
screen: 3%
mobile net in standby: 1%
etc.....

 

[belodion]

Is this a regular thing?

 

[ValerioRenna1]

Is this a regular thing?

It lasted 3 days, it stopped now