problem repairing imei gt i9500

hi i am trying to repair imei to a GT i9500 os 4.4.2 i already try the wipe efs, flash, repair service imei, flash method and no luck, and also i tried to write certificate but i cant, the wipe security button on the octoplus softwere doesnt wipe security, it repair network instead, and when i write certificate it said that the certificate its incompatible.