Diagnosis
Residue is trapped in the silicone sealing flap of the twist-to-open pour spout. This is a routine maintenance issue.
How to Fix It
1. Twist the spout lid to the 'open' position (align the unlock symbol). 2. Pull the entire lid assembly straight up off the pitcher. 3. Under warm running water, manually flex the clear silicone flap away from the plastic housing. 4. Use a small bottle brush or your finger to dislodge debris. 5. For a deep clean, the silicone flap can be gently peeled from its mounting posts for washing. Note its orientation for reassembly.
If That Didn't Work
If mold or stains are persistent, soak the disassembled lid and silicone flap in a solution of warm water and baking soda for 30 minutes. Do not use bleach, as it can degrade the silicone.
Heads Up
The pour spout must be in the 'open' position to remove the lid from the pitcher. Never try to pry it off while closed. Always dry all components thoroughly before storage to prevent mildew in the flap crevice.