Rockbros q5 tail light

Anybody have the same rear light?

I had this light for about 7 months now. I rarely use this because i dont go cycling at night.

I mainly use the smart light function when on roads. I charge it from time to time to avoid the battery getting drained.

I needed the light today but sadly the battery was empty. I charged the light two days before. But during those two days, i noticed that the battery indicator was on the whole time.

Now the battery isnt charging but it goes on when plugged to a power source.

Is there anyway to fix this?