DIAGNOSIS That’s the vacuum’s thermal cutoff light. The motor got too hot and it shut down to protect itself, likely from a clog or a full bin blocking airflow.
FIX Unplug the battery, empty the bin completely, and remove the wand to check for a blockage in the main airway. Let it sit for 30-60 minutes to cool down before reattaching the battery and trying again.
IF THAT DIDN’T WORK The filter might be saturated and causing the motor to overwork. Remove the washable filter (at the top of the bin) and rinse it under cold water until the water runs clear, then let it dry for at least 24 hours before reinstalling.
HEADS UP Never use the vacuum without both filters installed and completely dry—it can permanently damage the motor.