Howto Install Gapps on Galaxy J3 Pro Plus j3119s? I Have reset my phone and lost gapps
Does anyone know how to install gapps on  j3119s ?

I've tried everything but seems it doesn't work in this device


open gapps (flash from twrp)
gapps-5.1.x-20150404-minimal-edition-signed from XDA (flash from twrp)   
google installer (ussualy work on xioami china  ROM)
etc


I'm really frustated, help really appreciated...
One of my friend had the same issue in past, and ii resolved this issue by flashing new Firmware (The reliable and trusted solution). I have made a rough search for you and found following link with detailed instructions:

https://4frp.blogspot.com/2017/09/sm-j3119511-lollipopandroid-august-08-17.html

in case you have nay difficulty in process, let me know.

Before proceeding with the solution, download Samsung drivers from their official website from here and install. 

http://developer.samsung.com/galaxy/others/android-usb-driver-for-windows

Thanks