DIAGNOSIS The machine is recirculating dirty water because the recovery system is blocked, creating no suction. The main filter is either missing, wet, or clogged.
FIX Check the gray foam filter in the lid of the dirty water tank. Remove it, rinse it thoroughly under warm water until water runs clear, then squeeze out excess water and let it air-dry completely—this can take 24 hours. Never reinstall a damp filter. While it's out, also rinse the tank's float assembly.
IF THAT DIDN'T WORK There's a blockage in the suction path between the floor nozzle and the tank. Detach the nozzle and check for debris clogging the opening on the machine body. Use a long, flexible object (like a pipe cleaner) to clear any obstruction.
HEADS UP Running the machine with a wet filter is the #1 cause of this issue. It destroys suction. Always keep a spare, dry filter on hand to swap in while the other dries.