CU920 bad imei need help .

hi everybody , today i got 1 CU920 with the screen Show : unavailable OTP Block . i hit Z3x LG , and info exhibit :

Mode: Normal
Model: CU920
Build version: Feb 05 200815:39:02Feb 05 200814:00:00CU920
SW Version: CU915-MSM4090201D-V10h-FEB-05-2008-ATT-US
IMEI: BAD IMEI
BlueTooth Address: 0D:47:4D:7E:BB:01
Flash Name: toshiba_tya000bc00dogg
Flash Info: 0696/0040/0800

anyone who hit ever resolved this problem . pls support me .
thanks everyone .