My battery drains even when switched off!

[gorimapa]

Hello:
The batteryof my phone keeps discharging even when it is switched off. I've changed the battery of my phone three times and I am still having the problem.
I use Samsunggalaxy grand prime phone, android marshmellow 6.0.A

 

[Mooncatt]

The phone was released 5 years ago and no one is making batteries for it. Any "new" batteries are going to be old stock and have issues. I doubt you'll find one in decent shape.

 

[mustang7757]

Also try safe mode for extend time