Xperia ZR Bootloader (cm 12 problem), how do I flash the bootloader?

[AC Question]

Xperia ZR Bootloader (cm 12 problem)

How to flash bootloader on this phone???
i installed cm12 on this phone and after 12 hours it caused yellow screen and lines
i only has fastboot mode,
when it power on there all many horizontal lines on the screen, i tryed to flash bootloader but no succes
it says ''
sending 'bootloader' (169 KB)...
OKAY [ 0.014s]
writing 'bootloader'...
FAILED (remote: Command not allowed)
finished. total time: 0.045s
''
Help me