Error repair drk sm-g928i help me

Checking local file... OK
Searching server... OK
Compare local and server file... OK (up to date)
Searching USB Flash interface... COM39 detected
Setup connection... OK
Reading data from phone... OK
Sending data to phone... OK
Sending data to phone... OK
Waiting ADB device... OK
Reading phone info...
Recovery build version: 6.0.1
Boot version: G928IDVU4CRA1
Platform: exynos7420
Boot serial: 0215443131343138
Product board: zenlte
Initialization zTool... OK
Running zTool, please wait...
Start... OK
Initialization... OK
Generate and check client proof... OK
Verify proof by client... OK
Checking DRK status... NG!
Writing DRK... error ()
Done with Samsung Tool PRO v.33.2