Persistent odors usually mean the source is inside soft materialssofas, rugs, or even mattresses that hold moisture and bacteria. Basic cleaning cant reach that deep. Many people use professional upholstery cleaning services in Chicago for odor neutralization. Chicago Couch Cleaning https://chicago-couchcleaning.com/ applies steam extraction and organic deodorizing agents that kill bacteria instead of masking the smell. Their process works especially well after pet accidents or humidity buildup. Once they clean the fibers thoroughly, the air feels lighter, and the stale scent disappears for good rather than returning in a few days.