Usermod not found

    Hey all.
    I'm having issues with my keyboard/remote - Simplecom RT100

    Previously with Raspbian I had to run the below command to get it to work.

    sudo usermod -aG tty $username
    sudo su -c 'echo "KERNEL==\"tty[0-9]*\", GROUP=\"tty\", MODE=\"0660\"" >> /etc/udev/rules.d/99-input.rules'

    Now I'm not clued up enough within linux to work out why that made it work. I'm guessing it's something to do with the tty group?
    But when I run the command I get:

    -sh: usermod: not found

    The mouse part of the remote works, and the OK button works when the mouse is enabled - but the keyboard doesn't work at all.

    Can anyone shed some light on why this might be?

    Cheers :)

    Hunt

    In LibreELEC

    Code
    echo "KERNEL==\"tty[0-9]*\", GROUP=\"tty\", MODE=\"0660\"" >/storage/.config/udev.rules.d/99-input.rules


    but I doubt this will make any difference.