problem repair imxx U11

sir I try to repair the imei, but always error
*this equipment already repaired before
I always did, everything went well.
used version 1.38 and 1.37
Change flex etc etc

1. Checking phone connectivity.......
Phone connection confirmed!
HTC KEY CARD VERSION: 7
2. Checking Server connectivity...
Server connection confirmed!
3. Checking PowerAdapter connectivity...
Process started
PowerAdapter connected, processing request to adapter...
Starting operation...
Sending oem writeimei 357888888778773
... (bootloader) [ERR] Command error !!!
OKAY
finished. total time: 0.007s
htc_fastboot finished
Operation completed!
Releasing adapter.
Request completed


Starting PowerAdapter procedure:
Detected model: HTC U11 (Android 8.x)
Special recovery file is available
1. Checking phone connectivity.......
Phone connection confirmed!
HTC KEY CARD VERSION: 7
2. Checking Server connectivity...
Server connection confirmed!
3. Checking PowerAdapter connectivity...
Process started
PowerAdapter connected, processing request to adapter...
Rebooting to boot-loader:
Waiting for the phone...
Phone DISconnected
Phone connected [FA7B90500687] *** Fastboot mode
Phone DISconnected
Executing operation...
Starting operation...
Operation completed!
Releasing adapter.
Request completed