DIAGNOSIS: The station's dirty water tank isn't being emptied and cleaned frequently enough, leading to bacteria growth that re-soils the pads during washing.
FIX: Empty and rinse the station's dirty water tank after EVERY mopping session, without exception. Don't let dirty water sit. For the smell, run a deep clean: remove the mop pads and trays, fill the CLEAN water tank with fresh water and two tablespoons of white vinegar, then run a 'Clean Mop' cycle. Repeat with clean water only to rinse.
IF THAT DIDN'T WORK: The mop pads themselves are harboring bacteria. Soak them in a bowl of hot water with a cup of white vinegar for an hour, then machine wash them (without fabric softener) and air dry completely before reusing.
HEADS UP: The auto-wash feature is a maintenance reducer, not a sterilizer. You must still perform basic tank and pad hygiene weekly to prevent mold and odors.