Arguments Optional stuck on second test requirement

Tell us what’s happening:
My code is getting stuck on the second test requirement, addTogether(2)(3). when i print out args it returns [2] rather than [2, 3].

This code does not work using 2 separate arguments. args[i] = arguments[i] does not return [2, 3] when calling addTogether(2)(3).

Your code so far

function addTogether() {
  let args = new Array(arguments.length);
  for (let i=0; i<args.length; i++) {
    if (typeof arguments[i] !== 'number') {
      return undefined;
    } else {
      args[i] = arguments[i];

  if (args.length===2) {
    return args[0] + args[1];
  } else if (args.length===1) {
    let c = args[0];
    return ((x) => {
      if (typeof x!== "number") {
        return undefined;
      } c + x;


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Link to the challenge:

This is not a function call with the arguments. It is two separate function calls. The first call is addTogether(2). The (3) after the first part is the call to the function that the call to addTogether(2) should be returning.

Thank you so much for your explanation, it really helped. I now understand how the second function that I have is calling for the second function call from addTogether. Now I understand the code I wrote!!

The error in my code was just that i forgot to return c + x. Otherwise this works.