Some external pump heads will design a plastic buckle between the liquid outlet and the lower round cover at the beginning, which is used to fix it and prevent the pump head from rotating and causing liquid leakage during transportation. At this time, just remove the plastic buckle and rotate the pump head.
The external pump head may not spring up because there is a problem pressing the spring in the pump. At this time, unscrew the bottle cap and adjust the tightness of the spring to make the external pump head press the pump spring up again. You can also use tools such as hands or vises to screw and press the position below the pump until there is a click sound, which can also make it bounce back. The number of turns is not enough. Rotate it a few more times, or remove it to see if it is stuck somewhere.
