Thank you for sharing your concerns. Please may I check what you are doing to send items for print?
Are you plugging your USB into the desk top plutos (they look like half footballs)?
Are you plugging the usb direct into the printer (there is a usb port)
If there's a yes to either of these questions then this would be why as this function is disabled.
If this is not the case
then you need staff assistance to see it happen to assess what is happening. Please ask at the Customer Service desk