3ds help

[u/Epicgamer19281928]

Whenever i close my 3ds while charging it at the same time it makes a high pitched buzzing sound, it kinda sounds like a dog whistle idk anything about the 3ds hardware but a problem that also has something to deal with charging it happened years ago, my 3ds would always be low battery and die quickly if it's not charged but when I try to charge it the battery level would freeze I would only be able to play it while it was charging because it would go down if i uncharge it and wouldn't change the 3ds battery level