g928t okc 5.1.1 FAIL Write cert Done with Samsung Tool PRO v.23.8

Operation: Write CERT
Selected model: SM-G928T
Software version: 23.8
Waiting ADB device... OK
Reading phone info...
Model: SM-G928T
Android version: 5.1.1
Product code:
Phone version: G928TUVS2COKC
PDA version: G928TUVS2COKC
CSC version: G928TTMB2COKC
CSC country code: USA
CSC sales code: TMB
HW version:
Phone S/N: 00000000000
Modem board: SHANNON333
RF cal date:
IMEI:
Checking Super user right... true
Initialization AT RIL... OK
Checking certificate file... OK
KEY ID: 0784
Initializating zTool... OK
Running zTool, please wait... error (7.7.8)
Done with Samsung Tool PRO v.23.8