S8 plus battery draining

[ahmed1991w]

My s8 plus is draining battery very fast and heating. I replaced battery but it did not work. 

The mechanic said all other hardware is fine

All softwares are up to date. 

What can be the possible issue.

[NasirM1]

Dear kindly update its android version and clear the memory if your device is rooted

[ahmed1991w]

Its updated, how to clear memory?

[Saam_just_u]

Brother batry achi quality ki nhi hogi thats why

[ahmed1991w]

Sir original battery second hand hi milti h sirf karachi markets me. 4 batteries change ki hain phir bhi koi improvement nhi hai