OMG! YOU GOT MMBL??? Oh wow! Now you can flash nougat through pie roms! Esp since THE DEVELOPMENT COMMUNITY SWITCHED THINGS TO MAKING IT A REQUIREMENT TO BE ON MMBL!I bet you didn't had a j500h variant. So you can go and praise the guy. I won't. This is a stupid tutorial which makes no sense. OP literally has 0 clue on the H variant and posted this anyway. Because of OP I might have to just throw my j5 away since marshmallow is the worst thing ever happened to j5 series.
I agree with above, you probably could have gotten another variant who is able to run on the same network as you are now. I'm on the M variant, which is mainly a central and south american release. I'm on att network and it works for me, so it does back up the argument of get a different variant. But its ok, you can deal with it, figure out how to downgrade properly, or get a newer device.