honor 5x kiw-TL00H Problem 3g connexion

[firebird7880]

hey every body
i have honor 5x kiw-TL00H 3g dont work just 2g indicated all icon are activated 3g -4g but i work onely 2g
please help

 

[firebird7880]

i have tryied to flash other rom update.app but it stuck on 5% and show message instalation failed