fastboot oem unlock <UNLOCK_KEY> or on newer devices:

adb reboot bootloader fastboot oem get_unlock_data The command returns a string block similar to:

Note: Motorola often redirects this to a Lenovo support domain. As of 2025, the functional path is under the motorola-global-portal.custhelp.com domain. Not all Motorola devices are unlockable via the official site.