This looked appealing for long hikes, but a quick search for reviews revealed it’s not worth a buy.
Bought two of these and was immediately disappointed. There are no user manuals and even direct sunlight doesn’t charge them fully.
I’m sorry you’re having problems with the battery. Feel free to 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.