Slice and Splice code not being accepted

Tell us what’s happening:
For some reason the website is not accepting my code, but when i console.log(arr3); it seems that it is working fine. Is there something wrong with it that I am not seeing?

Your code so far

function frankenSplice(arr1, arr2, n) {
  // It's alive. It's alive!
  const arr3 = arr2.slice();
  return arr3.splice(n, 0, arr1);

frankenSplice([1, 2], ['a', 'b'], 1);

Your browser information:

User Agent is: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/75.0.3770.142 Safari/537.36.

Link to the challenge:

You have inserted arr1 into the position n instead of the elements of arr1. Also, splice returns an array of values removed, which in this case is an empty array. You want to return arr3 after the splice has taken place.