Boa Noite, esse é meu código, e quando aperto F8 o _balance do clientTwo mostra NAN, não consigo encontrar o erro e aposto que deve ser coisa mínima, mas preciso de ajuda, por favor!

class Client{ name; doc; }

class AccountCurrent{ agency; _balance = 0; // private

withdrawMoney(value){
    if (this._balance >= value) {
        this._balance -= value;
    }
}

deposity(value){
    if (value <= 0) return;
    this._balance += value;
} 

transfer(value, account){
    const valueWithdraw = this.withdrawMoney(value);
    account.deposity(valueWithdraw);
}

}

const clientOne = new Client(); clientOne.name = "Jessica"; clientOne.doc = 44455566677;

const clientTwo = new Client(); clientTwo.name = "Adriano"; clientTwo.doc = 33344455500;

const clientOneAccount = new AccountCurrent(); clientOneAccount.agency = 8888; clientOneAccount.client = clientOne; clientOneAccount.deposity(500);

const clientTwoAccount = new AccountCurrent(); clientTwoAccount.agency = 6666; clientTwoAccount.client = clientTwo;

clientOneAccount.transfer(200, clientTwoAccount); console.log(clientTwoAccount);