[not a kata issue]

your code fails a fixed test, here is the error message:

'Should handle negative numbers. For input n = -13, m = -13: expected NaN to equal +0'

which means your code returned NaN for that test. then your code fails any similar test during the random tests

so, you need to rework your code to handle negative numbers

JavaScript: Passed all tests but, after clicking Attempt it shows another 2 tests that are not passed