G928C DRK repair error

i have G928C DRK REPAIR ERROR hang on samsung logo PLZ HELP ME

MR_Blang


Checking local file... OK
Searching server... OK
Compare local and server file... OK (up to date)
Searching USB Flash interface... COM227 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: G928CXXS5CRH2
Platform: exynos7420
Boot serial: 0315344536363530
Product board: zenlte
Initialization zTool... OK
Running zTool, please wait... OK
Checking DRK status... NG!
Writing DRK... error ()
Done with Samsung Tool PRO v.34.6