No dataflash log after the first

Hi,

I have a strange behaviour here. I got only first log file recorded on SD card after formating on my PC. Never more than one file after that. My FC is MiniHawk. Annoying !

My sequence :
format SD
start FC, arm
test RC commands
desarm
download dataflash log ok
arm
test RC commands
desarm
Only first log visible

Any idea ?
I tried with two different SD cards.