It has Battery drainage

@yohannesta73930 you are really not giving us a lot of information here. All we can start with, is a pretty generic answer.

Make sure that your software is updated and that no apps are running in the background. Assuming that you checked your software/firmware, the next thing to do is to replace your battery. Use this guide Samsung Galaxy M31 Battery Replacement for that. After that, you do want to go ahead and replace the charging board as well as the flex cable from the charging board to the mainboard. Use something like this video to accomplish that.

Let us know what this does.