Flux blur update not working

Hi all, I plugged my friends flux blur esc into the my castle link to check the esc setting and do any updates but found that i was able to check and change things but unable to update the firmware in the esc im not sure if im doing it wrong it still got the 1.21 beta but unable to update it to the 1.26 final like i have on my and his other castle monster esc's.