Hand-wash only. Do not use the dishwasher.
Wash the pitcher, dispenser, lid, and reservoir by hand periodically using a mild detergent. Do not use abrasive cleaners. Rinse all parts thoroughly with water afterward.
If that didn't work because you have trapped water or film, for Pattern Series Pitchers, if water gets trapped under the sleeve, let the pitcher air dry upside-down at room temperature. For general maintenance, always allow the reservoir to empty before refilling, and don't keep the fill lid open for more than 5 seconds unless you are actively filling it with water.
Heads up: Keep the bottom of the filter in contact with the water in the pitcher to prevent it from drying out. If the filter dries out, you need to soak it in water for 15 minutes before using it again.