a) The milk unit may possibly be clogged with milk residue. Remove the milk unit and clean it under running water. You can also clean the milk unit with rinsing water. Run the "Intensive Cleaning" program (cleaning program for the milk system) as per your operating instructions. If possible, run the quick and hygienic "Easy Cleaning" program each time after dispensing milk by confirming the "Easy Cleaning?"display shown on the display twice using the rotary switch. The "Easy Cleaning" program prevents milk residues from being deposited and sticking in the milk hose and guarantees that your milk unit always remains hygienic. Perform descaling.
b) The ascending milk container tube may possibly not be connected properly to the lid. Check whether the ascending tube is connected properly to the lid.
c) The milk hose may possibly not be connected properly to the outlet and/or the milk container. Check whether the milk hose is properly connected.