@-stepan-: You need to enable Private Messaging. This is in the "Edit Options" of the control panel. If this isn't there, it has to be added somehow. You can try posting in
https://www.mobileread.com/forums/sh...d.php?t=319819 to ask it to be enabled, or contact a moderator.
But, you might be better to make an image yourself. That way it will have your serial number and you can configure the device before taking it.