System.IndexOutOfRangeException : clientside js to serverside c#

I'm trying to send some output from a client side Javascript code to a server side C# code.

But my current problem is, when i try to pass multiple parameters back to the server, then i receive the error:

System.IndexOutOfRangeException: The index was outside the array range. What could cause this problem?

Javascript part where I send the variables back to the server:

var tempStorage = {
    0: atmlist[index][i][0],
    1: betrag
};

API.triggerServerEvent(responseName, tempStorage);

The complete Javascript function:

atmSubMenus[index].OnItemSelect.coect(function (sender, item, i)
{
    if (atmlist[index][i][0] === 0)
    {
        API.triggerServerEvent(responseName, atmlist[index][i][0]);
        atmSubMenus[index].Visible = false;
        API.showCursor(false);
    }
    else if (atmlist[index][i][0] === 1)
    {
        var betrag = API.getUserInput("", 10);

        var tempStorage = {
            0: atmlist[index][i][0],
            1: betrag
        };

        API.triggerServerEvent(responseName, tempStorage);
        atmSubMenus[index].Visible = false;
        API.showCursor(false);
    }
    else if (atmlist[index][i][0] === 2)
    {

    }
    else if (atmlist[index][i][0] === 3) {

    }
});

And here's the C# part, which causes the error:

int betrag = (int)args[0];
sender.sendChatMessage("~y~[BANK]:~w~ Betrag: " + betrag);

And the complete function:

public void onClientEventTrigger(Client sender, string name, object[] args)
{
    if (name == "ATM_SELECTED")
    {
        int function = (int)args[0];

        if (function == 0)
        {
            int money = database.playerDatabase.getBankAmount(sender);

            if (money == 0)
            {
                sender.sendChatMessage("~y~[BANK]:~w~ Du hast kein Bank guthaben.");
            }
            else
            {
                sender.sendChatMessage("~y~[BANK]:~w~ Dein Bankguthaben beträgt: $" + money);
            }
        }
        else if (function == 1)
        {
            int betrag = (int)args[1];
            sender.sendChatMessage("~y~[BANK]:~w~ Betrag: " + betrag);
        }
        else if (function == 2)
        {
            sender.sendChatMessage("~y~[BANK]:~w~ Event 3 wurde getriggert");
        }
        else if (function == 3)
        {

        }
    }
}

I appreciate any kind of help.