Slice and Splice why not

JavaScript
#1

Tell us what’s happening:

I can’t understand why my code isn’t verifying, it works correctly.

Your code so far


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

console.log(frankenSplice([1, 2, 3], [4, 5, 6], 1));

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 6.3; Win64; x64; rv:68.0) Gecko/20100101 Firefox/68.0.

Link to the challenge:
https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/basic-algorithm-scripting/slice-and-splice

#2

first, splice changes the array on which it used
the challenge says that the input arrays should stay the same after the function runs

second, you are creating a multidimensional array, because you are inserting the whole array inside the other, not the single elements

as a beginner, looking at your code using Javascript Tutor is pretty useful - try it!

#3