The coffee machine door was opened unprompted during the descaling process.
Or the brew unit or containers were removed.
Start the descaling process again and follow the instructions on the display.
Refer to the operating instructions for the exact descaling procedure for your coffee machine.
A description of the procedure for descaling various coffee machines can be found in the article “Entkalkung starten und durchführen (Kaffeevollautomaten)”.
