XTC 2 Clip can not S-off for Butterfly 3 & HTC M9

When I used the XTC to S-off for HTC Butterfly 3 or HTC M9

I can not do it.

Please tell my why.

Sending oem writesecureflag 0
... (bootloader) HTC KEY CARD VERSION: 6
FAILPERMISSION DENY (DECREASE_CYCLE_FAIL)
FAILED (remote: PERMISSION DENY (DECREASE_CYCLE_FAIL))
Execution time is 7(s)
Operation finished