Custom binary blocked FRP on Samsung J2/j5/j7 and other Samsung model
Here is the simple way to solve this problem easily.
Download correct firmware of your phone.
Put the phone download mode(volume down+home+power key then press volume up key) and just flash it.
Wait for complete when complete,mobile will auto restart and you should add gmail account
If you have gmail just put and setup easily.
If you forgot your email you need to bypass it.
Way to bypass:-
By samsung box(z3x, octopus, miracle etc).
By pen drive with OTG cable.
By side-sync.