Help? Algorithms: Inventory Update

Tell us what’s happening:
several tests are failing when I submit this code, though when I check the output in a repl it seems to be correct. what am I doing wrong here?

Your code so far

function updateInventory(arr1, arr2) {
let stock = [...arr1];
arr2.forEach(i=> {
    let t = stock.findIndex(x=> x[1]===i[1]);
    if (t >= 0) stock[t][0] += i[0];
    else stock.push(i)
stock.sort((a,b)=> a[1] > b[1]);
return stock;

// Example inventory lists
var curInv = [
[21, "Bowling Ball"],
[2, "Dirty Sock"],
[1, "Hair Pin"],
[5, "Microphone"]

var newInv = [
[2, "Hair Pin"],
[3, "Half-Eaten Apple"],
[67, "Bowling Ball"],
[7, "Toothpaste"]

updateInventory(curInv, newInv);

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Challenge: Inventory Update

Link to the challenge:

you are missing this I would say

The returned inventory array should be in alphabetical order by item.

Being able to do the a > b is not supported. sort expect to get +1, 0 or -1 or at least a negative, zero or positive number. Not a boolean value

You need to use a comparison function which returns either 0 for items which are equal, -1 when item is is less than item b, and 1 when item is greater than item b.