Help me anyone about sm-g925i…

Hi to all…

I have a samsung sm-g925i handset, and there is android version 5.1.1, for this i want to write cert file, cert file i have, but its not getting root, after rooting it restarting on logo,

i tried to root by these softwares, but i its not getting root team

iroot
kingoroot
S6-UniBase_BOG8_v2

kindly help me
thanks