Did you check and see if any of the formatting has been altered or changed in the settings? If everything looks normal, try performing this procedure:
Auto Sense Procedure
1. Make sure you have configured your driver or application for the media type you are using. Gap/Web or Black Bar (Mark). Send a test print to the printer before proceeding so it is properly configured. Note: You can only send data when the button is green so cycle power if the printer button is red.
2 Turn off printer and have media loaded
3. Hold feed button down, and turn printer back on
4. When the red light starts flashing, release the feed button.
5. Printer light will turn green and advance a few blanks.
6. After printer stops advancing and prints the internal information, press the feed button one time.
7. You will get another label with the "Out of Dump" message on it.
Referenced from: https://km.zebra.com/kb/index?page=conte...