Chunky Monkey broken

Tell us what’s happening:
Why is this not working. works on codepen. let me pass.

Your code so far

function chunkArrayInGroups(arr, num) {
  for (var i= 0; i<arr.length; i+=num){
 return arr1;
chunkArrayInGroups([0, 1, 2, 3, 4, 5, 6, 7, 8], 4);

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36.

Link to the challenge:

all you are missing the keyword ‘var’ infront of arr1 to declare it in the local scope of the function. Then your code will pass.