how enable container on CHR\x86?

Hi,

funny I facing same problem on my RB4011iGS+5HacQ2HnD device. After executing “system device-mode update container=yes” command I did power on-off cycle with 5min, counting down on Terminal.

After trying to create new docker, Error pops out saying “Couldnt add Container - not allowed by device-mode(6)”
I tried to install docker on internal flash (>900MiB free).

Model:RB4011iGS+5HacQ2HnD
Firmware type: al2
Factory Firmware: 6.45.9
Current Firmware: 7.6
Upgrade Firmware: 7.6

Any thoughts what could be wrong?

Thanks, Rok