Smallest Common Multiple - can't understand why code doesn't work

Tell us what’s happening:

I don’t understand why my code is not working. It may not be the most efficent and I’m sure could be written better but it’s the principle of why it’s not working that has got me confused and why I’m posting!

For the tests in the exercise, it works for the first 4 but not for the last test (23 and 18).

smallestCommons([1, 5]) should return 60.
smallestCommons([5, 1]) should return 60.
smallestCommons([1, 13]) should return 360360.
smallestCommons([23, 18]) should return 6056820.

I’m wondering if it’s some kind of execution timeout that’s causing the code to fail?

Your code so far

function smallestCommons(arr) {
  console.log('arr', arr);
  var small = arr[0]; //smallest of the two numbers
  var big = arr[1]; //biggest of the two numbers
  var check = big - 1; // this is the lowest any common multiple could be
  var found = false;
  while (!found) {
    if (check % small === 0 && check % big === 0 ) { // if common multiple
      found = checkIfMultipleBetween(small,big,check);
  if (found) return check;

function checkIfMultipleBetween(small,big,check) {
  for (var between = small + 1; between < big; between++) {
         if (check % between !== 0) { // if not divisible by a number between
           if (small == 18) console.log('failed on ' + between);
           return false;
  return true;


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Link to the challenge:

You’re probably running up against the infinite loop protection because of how long it takes that test to run.

Ok, I was confused why I wasn’t getting some kind of console error as I thought there would be an error if this happened. I suppose it must be the reason.