fastboot oem get_unlock_data no response

I want to unlock the bootloader of my Moto X4 running Android 9 and get the unlock code. My computer is a Linux Mint Ideapad 3 (so should have USB-3 ports (referring to this post )). My device gets displayed when I type fastboot devices However, none of the 3 USB ports give me a response when I type fastboot oem get_unlock_data nor does the command finish. The bootloader logs say on the phone cmd: oem get_unlock_data. "**Allow bootloader get unlocked**" is enabled in developer options, and so is USB debugging. I need the unlock data to request on the Motorola page the unlock key.