N950U Rev4 Unlock FAIL

Have tried everything. Downgrade modem, factory reset, reflash software, flash combination. Always same error. Why? Other devices work fine so not problem with tool

[ 8/16/2018 10:43:15 PM ] Operation: Read Codes via Server
[ 8/16/2018 10:43:15 PM ] Selected model: SM-N950U
[ 8/16/2018 10:43:15 PM ] Selected port: COM39 SAMSUNG Mobile USB Serial Port
[ 8/16/2018 10:43:15 PM ] Software version: 33.5
[ 8/16/2018 10:43:15 PM ]
[ 8/16/2018 10:43:15 PM ] Checking Login and Password... OK
[ 8/16/2018 10:43:16 PM ] Ballance: 145 crd.
[ 8/16/2018 10:43:31 PM ] You have 145 credit(s) left. This operation takes 5 credits.Continue? Yes
[ 8/16/2018 10:43:33 PM ] Waiting ADB device... OK
[ 8/16/2018 10:43:34 PM ] Reading phone info...
[ 8/16/2018 10:43:34 PM ] Model: SM-N950U
[ 8/16/2018 10:43:34 PM ] Android version: 8.0.0
[ 8/16/2018 10:43:34 PM ] PDA version: N950USQU4CRF3
[ 8/16/2018 10:43:34 PM ] CSC version: N950UOYN4CRF3
[ 8/16/2018 10:43:34 PM ] Phone version: N950USQU4CRD7
[ 8/16/2018 10:43:34 PM ] Product code: SM-N950UZKACCT
[ 8/16/2018 10:43:34 PM ] CSC country code: USA
[ 8/16/2018 10:43:34 PM ] CSC sales code: CCT
[ 8/16/2018 10:43:34 PM ] Phone SN: R28JB2L52ZV
[ 8/16/2018 10:43:34 PM ] IMEI: 35850808
[ 8/16/2018 10:43:34 PM ] HW version: REV1.0
[ 8/16/2018 10:43:34 PM ] RF cal date: 2018.05.25
[ 8/16/2018 10:43:34 PM ] Chip name: MSM8998
[ 8/16/2018 10:43:34 PM ] Modem board: MSM8998
[ 8/16/2018 10:43:34 PM ] Security patch: 2018-06-01
[ 8/16/2018 10:43:34 PM ] Boot Warranty bit: 0
[ 8/16/2018 10:43:36 PM ] Waiting for device to become ready... OK
[ 8/16/2018 10:43:38 PM ] Initialization zTool... OK
[ 8/16/2018 10:43:41 PM ] Running zTool, please wait...
[ 8/16/2018 10:43:41 PM ] Start... OK
[ 8/16/2018 10:43:45 PM ] Initialization... OK
[ 8/16/2018 10:43:46 PM ] Generate and check client proof... OK
[ 8/16/2018 10:43:46 PM ] Verify proof by client... OK
[ 8/16/2018 10:43:46 PM ] Reading data from phone... OK
[ 8/16/2018 10:43:53 PM ] Searching Ramdump interface... COM9 detected
[ 8/16/2018 10:44:41 PM ] Reading data from phone... OK
[ 8/16/2018 10:44:45 PM ] Calculating... OK
[ 8/16/2018 10:44:53 PM ] Searching server... OK
[ 8/16/2018 10:45:30 PM ] Waiting for server answer... error (1)