Inside the transmission there is a part that moves to shift the gears. It has a small notch cut into it and when the transmission is in neutral that notch is supposed to allow the neutral switch to turn on.
The problem is, when the transmission is in neutral, the notch might not quite be lined up with the switch.
Just moveing the shift lever slightly up or down with your foot can move the notch to the right place to turn on the neutral switch.
The only way to know that this has happened is to watch the green neutral light.
When it comes on, the electric starter will work. If the light is still off, the electric starter won't work (unless you pull the clutch lever in).
Pulling in the clutch lever always allows the electric starter to work.