I havn't flown my drone in years but the battery shows it's fully charged with all green bars.When I put the battery in the drown and push the button on battery it lights up then shuts off.The battery doesn't show any signs of being swollen.When I take the battery out and push the button it shows it's fully charged so is it a battery problem or ?. The drone flew fine last time it was flown so i'm lost and any help is appreciated.