Flashing error

I am trying to flash my XPERIA NEO V to return it in 2.3.4 OS.
but this is what i got in flshtool.
2/037/2015 12:37:05 - INFO - Flashtool Version 0.9.19.0 built on 29-07-2015 12:00:00
22/037/2015 12:37:05 - INFO - Executing search strategies to find proxy selector
22/037/2015 12:37:06 - INFO - No proxy found for IE. Trying next one
22/037/2015 12:37:06 - INFO - Strategy firefox failed trying next one : No Firefox installation found
22/037/2015 12:37:06 - INFO - No proxy found for java. Trying next one
22/037/2015 12:37:06 - INFO - Syncing devices from github
22/037/2015 12:37:06 - INFO - Scanning devices folder for changes.
22/037/2015 12:37:14 - INFO - Pulling changes from github.
22/037/2015 12:37:15 - INFO - Devices sync finished.
22/037/2015 12:37:20 - INFO - Device connected in flash mode
22/037/2015 12:37:31 - INFO - Selected Bundle for SonyEricson Xperia Neo V (MT11i). FW release : 4.0.2.A.0.62. Customization : T-Mobile UK
22/037/2015 12:37:31 - INFO - Preparing files for flashing
22/037/2015 12:37:43 - INFO - Please connect your device into flashmode.
22/037/2015 12:37:44 - INFO - Opening device for R/W
22/037/2015 12:37:45 - INFO - Reading device information
22/037/2015 12:37:53 - INFO - Unable to read from phone after having opened it.
22/037/2015 12:37:53 - INFO - trying to continue anyway
22/037/2015 12:37:53 - INFO - Start Flashing
22/038/2015 12:38:07 - INFO - Processing loader.sin
22/038/2015 12:38:07 - INFO - Checking header
22/038/2015 12:38:07 - ERROR - Processing of loader.sin finished with errors.
22/038/2015 12:38:07 - INFO - Ending flash session
22/038/2015 12:38:07 - ERROR - Error in processHeader : 22 : The device does not recognize the command.
22/038/2015 12:38:07 - ERROR - Error flashing. Aborted
22/038/2015 12:38:10 - INFO - Device connected with USB debugging off
22/038/2015 12:38:10 - INFO - For 2011 devices line, be sure you are not in MTP mode

then i tried it again:

22/038/2015 12:38:40 - INFO - Selected Bundle for SonyEricson Xperia Neo V (MT11i). FW release : 4.1.B.0.587. Customization : Customized_NCB_Nordic
22/038/2015 12:38:40 - INFO - Preparing files for flashing
22/038/2015 12:38:53 - INFO - Please connect your device into flashmode.
22/039/2015 12:39:06 - INFO - Device disconnected
22/039/2015 12:39:09 - INFO - Device connected in flash mode
22/039/2015 12:39:10 - INFO - Opening device for R/W
22/039/2015 12:39:10 - INFO - Reading device information
22/039/2015 12:39:10 - INFO - Phone ready for flashmode operations.
22/039/2015 12:39:10 - INFO - Opening TA partition 2
22/039/2015 12:39:10 - INFO - Current device : MT11i - BX902QAYAA - 1255-1755_R1I - 1253-8237_4.1.B.0.587 - WORLD-i_4.1.B.0.587
22/039/2015 12:39:10 - INFO - Closing TA partition
22/039/2015 12:39:10 - INFO - Start Flashing
22/039/2015 12:39:10 - INFO - Processing loader.sin
22/039/2015 12:39:10 - INFO - Checking header
22/039/2015 12:39:10 - INFO - Flashing data
22/039/2015 12:39:12 - INFO - Loader : S1_Loader_Root_773f - Version : R4A069 / Boot version : R9A021 / Bootloader status : ROOTED
22/039/2015 12:39:12 - INFO - Transfer buffer size : 32768
22/039/2015 12:39:12 - INFO - You must have the according fsc script to flash this device.
22/039/2015 12:39:12 - INFO - Flashing finished.
22/039/2015 12:39:12 - INFO - Please unplug and start your phone
22/039/2015 12:39:12 - INFO - For flashtool, Unknown Sources and Debugging must be checked in phone settings

what is this error,

I am running JELLY BEAN V4 and superFUSION KERNEL i think. how can i fix this one?

please help.

thanks.