DIAGNOSIS This is a specific alert mode. Alternating green/red indicates a problem with the brush roll motor circuit.
FIX Unplug. Remove bottom plate. Inspect brush roll for free spin. Check the electrical connections to the brush roll motor. Ensure they are snapped in fully. Clear any debris. Plug in. If light persists, brush roll motor assembly is faulty.
IF THAT DIDN'T WORK The control board may have detected a fault. Unplug for 2 minutes to reset. If flashing returns immediately, board likely needs replacement.
HEADS UP This is not a user-serviceable error code. If basic reset fails, internal repair is needed.