It’s crucial that both the vacuum’s suction opening and suction cover are completely clean and unobstructed by dirt, dust, debris, or any other particles. Remove the suction cover and clean it thoroughly, by rinsing it and wiping it with a soft, dry cloth. You should also inspect the vacuum’s Deep Cleaning Brush, and ensure that nothing is stuck or entangled within its bristles, such as excessive dirt, hair, or other substances. Do not attempt to clean any flammable or toxic objects or stains, such as ammonia, chlorine, bleach, lighter fluid, gasoline, kerosene, etc. These substances can severely damage the StainZero’s internal circuity and suction mechanisms. Moreover, you should never pick up hard or sharp objects, such as glass, nails, or screws, as they may get stuck in the suction opening and damage the vacuum. If your floor, couch, or other surface has super-tough stains, then try spraying water on them if you haven’t already. Make sure the vacuum’s Clean Water Tank is full of clean water. Add a tiny bit of gentle detergent if necessary. Remember to check the Dirty Water Tank after each cleaning session, and empty it once it is full, as this could prevent the StainZero from properly cleaning any stains.