How to update S5 phone with Mali-T628

[b4bilal]

Hello,

I buy a phone from China the seller sell this to me as a original but i was unaware of that this is a Copy phone
so i just update this with Android 5.0 using Odin and after that everything work fine expect Sim network its show "Not registered on network"
I have try all the solutions available on internet for this and update back to Android 4.4.2 but still the same issue "Not registered on network"

So i just think that this one need a customs ROM made for China copy mobile only and i have download many ROMS and try to update them with SP flash tool but this one not detected the phone because i think the GPU use in this phone is Mali-T628; ARM; OpenGL ES-CM 1.1; OpenGL ES 3.0

Here are the phone specs:
CPU 8 cores; universal5422 exynos5; Max: 1300,0 MHz; Min: 500,0 MHz
Display 1920 x 1080; DPI: 480; Evaluated Size: 4,6"
GPU Mali-T628; ARM; OpenGL ES-CM 1.1; OpenGL ES 3.0
RAM 2048 MB (2026 MB available)

So if anyone please tell me what should i do.

Thanks