Finally solved. So i answered my own question. First u need to unlock the bootlocker via the unlock website. I waited 2 days for approval. then u need to flash the latest china baseband to ur stable global rom to fix the issue!!
download adb and fastboot program files and put in a folder, download the china rom and extract the NON-HLOS.bin from the china rom into the same folder as adb.exe and fastboot.exe
Run Command window to ADB (Fastboot).
fastboot devices
(This command will list the connected phone If the serial number. your phone is displayed, you can start the process of firmware).
fastboot erase modem
(to cleanse the phone from the modem firmware and settings). If the process will take - will write OKAY)
fastboot flash modem NON-HLOS.bin (wait for the process OKAY sign).
fastboot reboot (restart the system).
I tested on all networks!! Including the new Circles.life and the 4G is damn fast!!! finally didn't regretted not to sell this piece of power mi5 pro~~!
Yeap, 4g works perfectly! Wish I knew about this when I got it.
4g works when on global rom, just that it is super unreliable