The dirty water tank is filled with dirty water. The filter and brush are filled with dirt, hair, and other things.Recommended action:
Empty the dirty water tank. Clean the filter (remember to open the lid and clean underneath), air channel inlet, and the brush (you can use the knife which is already in the hard floor nozzle). Add 50 ml of clean water in the tray, start the machine, and let it run for 30 seconds. The pips within the machine will be clean.
Always take the brush out of the nozzle and place it vertically on the tray for drying.