cert file for G925F needed

hi could anyone please provide me with a cert file for G925F? needed desperately, have chimera tool ready to go but no cert file…. its for my own phone, I am in the uk and have imei stuck as 350000000000006…

If someone could give me one or tell me where I could find one Id be eernally grateful as I have no phone just now, just "not registered on network" issue due to imei and I have no efs back up.. please help, thanks, Elijah