N920T 5.1.1 wirt cert

Operation: Write CERT
Selected model: SM-N920T
Software version: 24.2

Waiting ADB device… OK
Reading phone info…
Model: SM-N920T
Android version: 5.1.1
Product code: SM2N920TZKATMB
Phone version: N920TUVS2COKC
PDA version: N920TUVS2COKC
CSC version: N920TTMB2COKC
CSC country code: USA
CSC sales code: TMB
HW version: REV0.2
Phone S/N: RF8GB0B25TL
Modem board: SHANNON333
RF cal date: 20151104
Checking Super user right… true
Initialization AT RIL… error

Done with Samsung Tool PRO v.24.2

am i doing something wrong ? or this phone can’t be done ?