This is also the case for me. However, I have noticed that when the green light is on, it is charging. However, it also lights up when the sky is overcast. But then the charging is minimal. My device needs 2 days of full sunshine to charge from 0 to 100 %. But I am still satisfied with it. To charge 2 mobiles, it only needs a quarter of the stored energy. In the grand scheme of things, it's more of a gimmick, but at least we're doing something about the energy shortage, albeit in small steps. Kind regards Heinz