I have held down the button underneath the light until I have seen four flashes of the lamp. There is never a fifth flash. I then turn off power to the light (by turning off the bike or using the headlight button on my controls) and turn it back on. If it is night, the light appears to go into night...

Hello, Appologies for using English. I have a giant Quick e+ 2018. I added a lupine SL S to this bike in October 2018. The light was working fine during the winter season when it was very dark. Recently I was trying to ride the bike at night but the light shuts off after 16 seconds. I can toggle the...