Lock bootloader problem

[Kris Groove]

Hello,

today I unlock bootloader to install EX Kernel, after few test I back to stock boot img and try to lock bootloader but I have:

fastboot oem lock                                                         
(bootloader) slot-count: not found
(bootloader) slot-suffixes: not found
(bootloader) slot-suffixes: not found
...
(bootloader) WARNING: This command erases all user data.
(bootloader) Please re-run this command to continue.
OKAY [  0.051s]
finished. total time: 0.051s
fastboot oem lock
(bootloader) slot-count: not found
(bootloader) slot-suffixes: not found
(bootloader) slot-suffixes: not found
...
(bootloader) Flash valid Android images now
(bootloader) Then re-run this command to lock
OKAY [  0.052s]
finished. total time: 0.052s

My soft: