Why It won't turn on after upgrade?

Few days ago I tried to upgrade my Samsung Galaxy grand prime duos phone to lollipop version 5.0.2 from KitKat 4.4.4 but unfortunately after the installation it is showing Samsung logo but it won't booting up and I couldn't get the home screen. I tried every thing what I can, I took the battery out and keep it for a while and replace that. I tried hard reset also but is that anything not worked Finally I gave it to a repair center also but I didn't get that work. Please help me with this