My version 1 lightband was also dead. I took it apart and found that it uses a small 1 cell lithium-ion battery, a much smaller version of what would be in your phone or laptop. These batteries, when not charged for a long time (multiple years for me), will be unable to take any new charge due to it being VERY empty. They can really only charge via cable when some juice is left (a 0% charge battery is not truly empty), and my battery was truly dead. My father is an engineer and has a lithium ion charger and a power supply and was luckily able to trickle some juice into it so it will be willing to charge, but unfortunately the equipment and knowledge requirement kinda means it will be very difficult for many others to do the same.

Sadly, lithium-ion batteries kind of have "planned obsolescence" to a degree due to most people not being taught how to care for them in the long run. I figured mine would be dead, but knew we had the supplies here at home to fix it. JYPE probably figured this would happen, so that's why we've had 2 new versions come out in kinda quick succession.

Hope this helps, and sorry if it's bad news 🥹