**Tell us what’s happening:**

Can anyone please help to find out error of this code

**Your code so far**

```
function multiplyAll(arr) {
let product = 1;
let sum="";
// Only change code below this line
for (let i= 0; i < arr.length; i++) {
for(let j= 0; j< arr[i].length; j++) {
sum = product* arr[i][j];
}
}
// Only change code above this line
return sum;
}
multiplyAll([[1, 2], [3, 4], [5, 6, 7]]);
```

**Your browser information:**

User Agent is: `Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/113.0.0.0 Safari/537.36`

**Challenge:** Basic JavaScript - Nesting For Loops

**Link to the challenge:**