N950U ATT read code failed

Checking Login and Password... OK
Ballance: 5 crd.
You have 5 credit(s) left. This operation takes 5 credits.Continue? Yes
Waiting ADB device... OK
Reading phone info...
Model: SM-N950U
Android version: 8.0.0
PDA version: N950USQS5CRG9
CSC version: N950UOYN5CRG9
Phone version: N950USQS5CRG9
Product code: SM-N950UZVAATT
CSC country code: USA
CSC sales code: ATT
Phone SN: R38J80HMGHZ
IMEI: 351823090298100
HW version: REV1.0
RF cal date: 2017.08.19
Chip name: MSM8998
Modem board: MSM8998
Security patch: 2018-08-01
Boot Warranty bit: 0
SIM State: ABSENT
Waiting for device to become ready... OK
Initialization zTool... OK
Running zTool, please wait...
Start... OK
Initialization... OK
Generate and check client proof... OK
Verify proof by client... OK
Reading data from phone... OK
Searching Ramdump interface... COM59 detected
Reading data from phone... OK
Calculating... error (0)
Done with Samsung Tool PRO v.34.0



what problem?