Solved! laptop battery problem : fully charged when plugged but shut down when unplugged

Oct 9, 2018
Before start, I'm using msi laptop GT62VR 6RD.

One day, my laptop battery started to show "fully charged" whenever charger plugged.
But as soon as I unplug the charger, laptop's battery LED turns to red and shut down immediately.

I think this problem comes from wrong battery indicator. What should I do?