Use the Rest Operator with Function Parameters Button not working

Tell us what’s happening:
I am trying to Run The Tests but even after clicking hundreds of times it is not testing it and the button is not working don’t know why.

Your code so far

const sum = (function() {
  "use strict";
  return function sum(...args) {
    const args = [...args];
    return args.reduce((a, b) => a + b, 0);
console.log(sum(1, 2, 3)); // 6

Your browser information:

User Agent is: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:60.0) Gecko/20100101 Firefox/60.0.

Link to the challenge: