Can you hear the pump trying to work? Do you see any fluid on the ground, or see any fluid on the reservoir (possibly leaking out)? If you can hear the pump working, but nothing is happening, you may also want to check the coupler where the hose and the nozzles connect to each other. Mine were gunked up and, after removing and cleaning, sprayed much better (although they sprayed anyways, I just saw the spray somewhat diminishing).