DIAGNOSIS This alert means the robot's extractors stopped because the Clean Base failed to engage its suction during an expected empty cycle, often due to a communication hiccup.
FIX Cancel the current job from the app. Manually place the robot on the Clean Base. Listen for the emptying cycle to start. If it does not, unplug the Clean Base for 30 seconds, then plug it back in. Restart the cleaning job.
IF THAT DIDN'T WORK Check the robot's bin is fully seated. Remove it and reinsert it until it clicks. Ensure the Clean Base's bag is properly installed and not overfull (the fill line should not be visible).
HEADS UP This is often a transient software error. Ensure both the robot and Clean Base firmware are updated in the iRobot app under Settings > Product Settings.