DIAGNOSIS: The most common cause is a partial clog in the suction pathway between the robot's dock port and the station's bag, or the dustbin lid isn't opening fully during docking.
FIX: First, check and clear the obvious: remove the station's dust bag and check its neck for a clog. Then, inspect the rubber seal around the robot's dustbin lid for debris. Manually open and close the lid a few times to ensure it moves freely. The main fix is to clean the dock's suction port on the station with the small brush tool provided, focusing on the rectangular opening.
IF THAT DIDN'T WORK: The station's internal suction motor filter might be clogged. Remove the water tank (if full) and the dustbag, then locate and remove the small foam filter inside the station. Rinse it under water, let it dry COMPLETELY for 24 hours, and reinstall.
HEADS UP: Never use the station to empty wet debris or large clumps of pet hair. This will instantly create a hard clog in the tubing that's difficult to clear.