Labels pass through the printer machine, but are always blank.
This is most likely caused by the wrong label type being installed in the printer. In this case it is that a Thermal-Transfer label type that requires ribbon be used in the print process has gotten mixed in with the other labels. Most Cubiscan systems employ a Direct-Thermal label type which is made of material that changes to black when it is heated up. An easy way to check the label type is to swipe a fingernail across the label surface to see if it changes color due to the friction heat created. If it remains white, it is a thermal transfer label, and the print process will not work on it.
Solution: Change the roll of labels out, and install the correct label type. Dispose of or return the improper label stock if possible to ensure it isn't installed on the machine by mistake in the future. If your system does indeed use Thermal-Transfer labels, ensure that there is ribbon installed properly in your machine, and retest.