Primary causes: empty water tank, tank not locked, or the machine hasn't reached temperature.
- Check the water tank. Fill it to MAX if empty.
- Push the water tank down completely until it locks into place.
- Allow time for the machine to reach operating temperature after pressing the STEAM button.
IF THAT DIDN'T WORK:
- The machine likely needs descaling. Perform a descale cycle.
- The steam wand tip may be blocked and need cleaning.
HEADS UP: Briefly purge the steam wand before texturing milk. Press the STEAM button to start purging, then press it again to stop.