Tracker always shows low battery and now will not track at all

Recently one of my trackers started showing a low battery indicator despite being charged overnight on a standard USB charger hub while my other trackers would be perfectly charged one of my trackers would not. However, despite showing a low battery indicator it would continue to run without issue, now it’s refusing to track at all and continues to show a low battery light. It’ll connect to my SW7 dongle but does not track at all.

Does it still power off when holding the system button?

Yes, it still powers off correctly.