The brushes have stopped rotating in the main head.
If I attach the upholstery head those brushes rotate.
Have you checked the dirty water tank is properly fitted and empty? If so, the problem could be caused by the float valve inside the tank that shuts off the suction when it detects the tank is full, This float valve may be jammed up by crud and not dropping back down. Give this a good clean and see if this helps..
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