I was so happy with this headlamp. After only 2 day of light/normal use it quit working. 
I even fully charged the battery, but still, nothing. So, idk what the issue is but, what can ya do!? 
I’m so sorry. Please reach out to Woot! Customer Service.
From a browser, use the Woot! Customer Service form.
In the Woot! App, choose Account from the bottom navigation and then Support.
Note: Woot! Customer Service replies go to the email address on your Woot! account, not your Amazon login email if used/different.