SM-G935F unlock failed z3x

Hi, I have a problem with G935F Android 7.0

Operation: Read Codes
Selected model: SM-G935F
Software version: 31.0

Searching Samsung modem... detected COM17
Reading phone info... OK
Model: SM-G935F
AP version: G935FXXU2DRB6
CSC version: G935FXEO2DRB6
CP version: G935FXXU2DRB6
Product code: XEO
Phone SN: R58H75xxxxx
Unique number: CE041604682EC20602
Reading IMEI... OK
IMEI: 357xxxxxxxxxxxx (SIGN: NG_NONE)
Checking hash file... OK
Reading data from phone... error (0)
Try downgrade modem if possible
Done with Samsung Tool PRO v.31.0

I try many solution from forum and no results. Downgrade modem phone lost imei and box no recognize it....with root it same. I try several versions of program and on two computers.

Please help
Best Regards