I know this is a stretch

hi!, so recently my laptop has come across an issue, so my battery charges up to around 95-96%, but the battery does not charge until its way lower in battery, why this is an issue is that games run at 30 FPS when its not plugged in, and since it stops charging/not using my AC Adapter/Power Cord, all games run at 30 fps, I was hoping that maybe some of you on league have had/fixed this issue, or even know quite a bit about computers and can guide me the correct way, thanks!