G935F NEW SEC BIT 2 Unlock ERROR

new phone, new sec, knox 0x0000

logs :

READ CODES DIAG

Please wait, generating hash codes file, this can take few minutes... OK
Searching Samsung modem... detected COM745
Reading phone info... OK
Model: SM-G935F
AP version: G935FXXU2DRB6
CSC version: G935FVFG2DRB1
CP version: G935FXXU2DRB6
Product code: CNX
Phone SN: RF8JA1xxxx
Unique number: AD061703BC980AC3E7
Searching Samsung diag port... detected COM746
Reading phone info... OK
CP version: G935FXXU2DRB6
CP build: Feb 14 2018 13:11:42
Reading data from phone... error (1)

Done with Samsung Tool PRO v.31.0

whats to do ?

thanks