After use, empty and clean the bottle and flush the sprayer thoroughly with warm water while pressing the trigger, then slide the safety switch to the LOCK position. Replace the bottle cap.
The nozzle and/or the the pickup tube filter may be partially blocked. Remove the nozzle by twisting past the X marker. Flush it with warm water and twist the nozzle back onto the sprayer.
Check that the paper isolating the batteries has been removed, that the batteries still have charge remaining and have been correctly loaded into the battery hatch on top of the sprayer.
When storing, changing liquid in the bottle or changing batteries.
Check that there is enough liquid in the bottle for the tube to be fully immersed in the liquid and open the white nozzle slightly.